CHAPTER X. 255

PARASITES DURING THEIR WHOLE LIFE.

In this chapter we bring together true parasites, which may be called complete; they pass every part of their life under the care of a neighbour, and require an asylum the more urgently, since they cannot exist without it. They absolutely need both food and lodging. Not long ago, all parasites were supposed to be dependant during their whole life, and to be incapable of living outside the body of another animal. We have before proved that this opinion was erroneous. We find in this category a great number of parasites which may be separated and placed in the first group, including all such as pass all the phases of their life on the same animal, without changing their costume, and many of which never leave the fur, the feathers, or the scales, among which they are born.

Fishes nourish on the surface of the skin a great number of these, which helminthologists have thought proper to classify under the name of _Ectoparasites_. Among many crustaceans and insects, only one of the sexes is parasitical. The males remain entirely free, and preserve all their attributes, while the females seek for assistance, and require food and lodging. The female alone sacrifices her 256 liberty, and changes her form entirely in order to secure the preservation of her posterity.

The insects called _Strepsiptera_, which live as parasites on wasps, furnish a curious example of this (Fig. 77). These insects, the _Polistes_, the _Andrenæ_, and the _Halicti_, do not kill the larvæ of the Hymenoptera on which they feed; they suck the blood of their victim slowly, and leave him just enough strength to go through his metamorphoses. The females are condemned to remain almost completely immovable on their prey, while the males are winged.

Naturalists have paid great attention to these latter insects, as much on account of their mode of life as of the difficulties which they have suggested to entomologists in the appreciation of their natural affinities. Are they coleoptera, as was for a long time, and perhaps correctly, supposed, or do they form a distinct order by themselves? However this may be, these are the facts known concerning them, according to the recent observations of Mons. Chapmann, a conscientious naturalist. The females do not lay their eggs in the nests of wasps, but the larvæ, under the form of meloë, penetrate into the cells, by the assistance of the larvæ of the wasps, which carry them hidden between the second and third ring. The larvæ of the 257 Rhipiptera are developed at the expense of the larvæ of the wasp, suck their blood, swell, and their skin remains adhering to the fourth segment.

When the rhipipterous insect is six millimètres in length, it changes its skin the second time, and this splits on the back, so that the 258 skin remains fixed between the larva of the parasite and that of the wasp. It then sucks the rest of the juices of the young wasp, and becomes a nymph in the prison which it has formed for itself. This evolution lasts from twelve to twenty-four hours.

Many male crustaceans, though they differ materially from their females in form as well as in manner of life, do not remove far from their partners in order to procure the assistance which they need. The insects which now occupy our attention are entirely different in this respect. The male preserves his usual appearance during the whole of his life, as well as the attributes and independence of free insects; while the female seeks for assistance with regard both to food and lodging from the time she leaves the egg; she is still wrapped up in swaddling clothes when she receives the male, as when she came forth from the egg.

The worms of this category are usually fully formed without undergoing metamorphoses; and if the place which they choose at their exit from the egg is not precisely their cradle and their tomb, at least all the phases of their monotonous life occur around it. They may be ranked among the most beautiful and the largest of parasitical worms; and as they are hermaphrodites, we find no greater diversity in the several forms than in their differences of age. All have their reproduction certain, and their eggs are less numerous for this reason. There are some of them that lay only one egg at a time, and this egg sometimes appears but once during a season. This explains why the eggs of some of these worms have not yet been recognized.

We may place at the head of this group the _Tristomum_, which has 259 only been discovered a few years. We owe to Baster the knowledge of a beautiful and large species, which inhabits the body of the halibut. Naturalists have given it the name of _Epibdella_. This worm is of the size of the human nail; it resembles in form a box leaf; by the aid of its suckers it clings to the skin of its host like a scale; and is sometimes mistaken for one. It is of an oval form, and of a dull white colour; it can scarcely be distinguished from the skin of the fish. We may have it before our eyes for a long time before we perceive it.

Another Epibdella lives on the skin and on different parts of the body of the European maigre, or the Virgin Mary's fish; it is covered with pigment spots which cause it still more to resemble the large scales of its host. This fish, which is also called the _Sciæna aquila_, has its skin covered with similar scales, and they are of the same colour, both on the back and belly.

Another large and fine worm of this group lives on the gills of the sturgeon, and is distinguished by its suckers as well as by its great mobility. The epibdellæ preserve their scale-like form during their greatest contractions, but these worms change with every movement. The _Nitschia elegans_, for such is the name by which it is distinguished, is not rare on the sturgeon as we see it in our markets. Among the many parasites in this category, there is a very remarkable one which deserves particular mention. It lives abundantly on fresh-water fishes, preferring to attach itself to their gills; it is found most commonly on the bream. For our knowledge of these worms we are indebted to Nordmann.

They bear the name of _Diplozoon paradoxum_, and are always double, 260 that is to say, always united like Siamese twins, being organically fastened together; they leave the egg, like their congeners, isolated and hermaphrodite, instal themselves separately on their host, and a little time after their choice of a resting-place, they unite so that the tissues, I was about to say the organs, are welded to each other. They cross like two strokes of an _x_. It is in this position that they live and die, after having produced large and beautiful eggs provided with a very long cable. These eggs are laid separately, and attached to the gills of the fishes which give them shelter. At the end of a fortnight the ciliated embryo comes forth, being provided with two eyes, and seeks to establish itself on a fresh host.

Under the form of _Diporpa_ it has a ventral sucker, and a small papilla on its back, and the two individuals are attached to each other cross-wise by the sucker and the papilla. Notwithstanding what Humboldt says in his "Cosmos," the _Diplozoon_ is not an animal with two heads and two caudal extremities, but is a double animal, two hermaphrodite individuals united, which at first have lived separately, and have become soldered to each other at the period of maturity.

We find a nematode, and consequently an animal with the sexes separate, which presents the same phenomena. The male and female are soldered together, but the female alone undergoes development. It is the _Syngamus trachealis_ of Siebold. It inhabits the tracheal artery of some gallinaceous fowls, and according to recent experiments, it develops itself directly in the tracheal artery of birds.

Another beautiful trematode, the _Octocotyle lanceolata_, lives 261 abundantly on the gills of the alosa, and another, the _Octobothrium merlangus_, on those of the whiting. The gills of the _Mustelus vulgaris_ regularly bear another species resembling a leech, but instead of a single sucker there are six; this is the _Onchocotyle appendiculata_.

The bladder of frogs lodges a very beautiful and large trematode which has lately been studied by many naturalists, the _Polystomum integerrimum_. Many observations remain to be made on the different phases of the existence of this parasite. Its organization is known, and it has been seen to lay large and beautiful eggs, but its movements have not been observed before its entrance into the bladder.

This Polystomum of the frog--and it is no doubt the same with the species _Polystomum ocellatum_ which inhabits the mouth of the European tortoise (_Emys Europæa_)--lays eggs only in winter, and the eggs of the young ones do not seem to produce more precocious embryos than those of the adult. The embryos are ciliated, unlike those of many of the ectoparasite worms. They much resemble the gyrodactyles, especially by their bristles; and like these, they inhabit the cavity of the mouth before they migrate into another organ. We may even ask if these singular gyrodactyles, so peculiar in many respects, are not the larval forms of trematodes allied to the polystomum.

Several important works have lately appeared on the _Polystomum integerrimum_, by Mons. Stiéda in 1870, by Mons. E. Zeller and Mons. Willemoes-Suhm in 1872.

The gyrodactyles, which we have just mentioned, are among the most 262 curious worms that have been discovered during late years. They are of small size, and live in the gills of fishes, often in great numbers, and move with considerable agility. They are armed with very variable hooks, which serve to anchor them; and sometimes a digestive canal and organs of sensation are found in them.

The _Gyrodactylus elegans_ bears within it a young one which already has hooks, and in this young one, which is not yet born, we see another generation with the same organs, so that three generations are thus enclosed. The daughter is ready at the moment of her birth to give birth to another daughter. According to another mode of interpretation, the mother and daughter are sisters; the elder is found at the periphery, the younger at the centre. These worms are found abundantly in the gills of the cyprinidæ, or white fishes. We have only to scrape gently the surface of the gills with a scalpel, and thus remove a small quantity of a mucous substance, place it on a slide of a microscope, cover it with thin glass, and examine it immediately with the compound microscope. We cannot repeat this three times without finding gyrodactyles.

There are also many insects which live as parasites on plants, and demand from them both a resting-place and their food. Almost all the Hemiptera are among these; we have already mentioned them. The hemiptera, which live on the sap of vegetables, are parasites in the same manner as those which live at the expense of animals. We ought not to make a difference between the manner of life of the bugs of plants and those of animals. It may be said that Providence has placed these beings as riders on both the vegetable and animal kingdoms to 263 restrain them with a bridle. What the gardener does to plants, the aphis has often done before in order to arrest a too vigorous and rapid growth.

The cochineal insect (_Coccus cacti_) Figs. 80 and 81, originally 264 from Mexico, lives on the cactus nopal as a true parasite, and furnishes a precious colouring matter, carmine. This insect has been introduced into the Antilles, Spain, the Canary Isles, Algeria, and Java.

Lake is produced by a species of the same genus, originally a native of India (_Coccus lacca_).

Aphides (Fig. 82) feed on the sap of plants; they multiply rapidly without the male insect. Rose-trees, and more especially their buds, are attacked by a species of a green colour, of which we give a representation (Fig. 83).

An aphis, the _Phylloxera vastatrix_, has, a short time since, invaded the vineyards, and small as it is, it is dreaded as a plague which scatters ruin in its path. According to recent observations this insect has a double series of generations which precede each other: the mother type and the tubercular type. But this polymorphism seems to be more apparent than real, although there is a considerable 265 difference in their manner of life and of procuring nourishment. Is this difference the result of the different kinds of food taken from the roots and the leaves? There is one thing which may reassure us as to the future attacks of the phylloxera, that Mons. Planchon has 266 just discovered in America the cat of the phylloxera, one of the acaridæ, its mortal enemy; and it is only necessary to multiply these in order to destroy this terrible pest of the vineyards. We thus see that we have only to imitate this so-called blind Nature, in order that we may arrest a misfortune against which man is unable to protect himself by his own powers.

We will here repeat what we wrote respecting aphides some years ago. Who does not know these small green bodies, of the size of a pin's head, coming like a cloud upon the buds and leaves of the rose bushes, which shrivel and wither immediately? There are green ones on certain plants, and black ones on others, but whatever be their colour, they are living pearls which form garlands round the stalk. The world considers them as vermin, and they scarcely dare to touch them with the point of their fingers. To the naturalist they are a little world of wonders. Let us examine with a magnifying lens these walking grains of sand; each grain will reveal to us a charming insect, whose head is adorned with two little antennæ, and has globular projecting eyes glistening with the richest colours; behind these are two reservoirs of liquid sugar, elegantly mounted on a polished stalk, and always full; long and slender limbs support the globular body.

Much has been written about these small sugar manufactories, so well known by ants that they have procured for the aphis the name of ant-cow. Among the curious phenomena presented by these grains of animated dust, that which most interests us relates to the secret 267 of their astonishing, we may say, their prodigious fecundity.

Nature requires millions of aphides in a few hours, to arrest the exuberance of vegetation, and as if she distrusted the assistance of the male insect, she dispenses with it, and the female brings into the world a daughter already prepared to produce a grand-daughter. Generations succeed each other with such rapidity, that if the daughter at her birth were to meet with any obstacle in her passage, the grand-daughter might come into the world before her mother; a single egg can produce in the course of one season milliards of individuals. Each plant has its own aphis, and in many localities the ravages of the _Aphis laniger_ are but too well known, though it was unknown in Europe a quarter of a century ago.

The _Gyrodactylus elegans_, of which we have spoken above, contains embryos similarly enclosed, and if these facts had been known at an early period, the celebrated theory of the enclosure of germs, so warmly advocated by Bonnet, would have preserved still longer its intrepid defenders.

With but few exceptions, all the Hemiptera are parasites of the vegetable kingdom. There are only very few which attack animals. There is one species, the name of which may be readily guessed (_Acanthia lectularia_), which pursues us relentlessly everywhere, for it will wait for months and years, always equally greedy of our blood. It surprises us during the night, and does not wait till its digestion is complete before it attacks us again. Happily for us, another hemipterous insect, the masked reduvius (_Reduvius personatus_) penetrates like the preceding one into our apartments, and covers 268 itself with dust, in order the more readily to fall upon its enemy; but man is not sufficiently acquainted with its habits, to make war in common with it on this miserable parasite. We ought for this purpose to place the masked reduvius under the protection of the law, to collect the various kinds together, and to offer premiums for the most vigorous races.

INDEX. 269

Acanthia lectularia, 267 Acaridæ, 130 ---- of reptiles, 135 ---- insects, 135 ---- molluscs, 136 Acarus, itch, 131 ---- eruditus, 137 ---- marginatus, 134 Actinia carcinopodus, 63 Adamsia, 26 Agamonema, 234 Alardus caudatus, 45 Albertia, 35, 78 Alciopina, 47 Alcyonium domuncula, 27 Alepas on Spinax niger, 58 Allotria victrix, 172 Amphinoma, 43 Amphistomum sub-clavatum, 203 Ampularia and Sphærium, 40 Ancei, 72 Anelasma squalicola, 58 Anemone of Chinese sea, 7 ---- and Pyades, 26 Angler (fishing frog), 33 Anguillula macroura, 248 ---- scandens, 181 Anguillulina, 182 Anilocra, 29 Anodonts, young, 39 Anoplodium parasita, 46 Apterychtus ocellatus, 6 Arcturus Baffini, 41 Argas chinche, 133 ---- Persian, 133 ---- reflexus, 143 ---- Americanus, 134 Arguli, 34, 72 Arius bookei, 8 Ascaracantha tenuis, 250 Ascaris acus, 241 ---- inflexa, 237 ---- lumbricoides, 95 ---- megalocephala, 241 ---- nigro-venosa, 157 ---- vesicularis, 237 Ascaroides limacis, 83 Asellus medusæ (Dalyell), 21 Asilus crabroniformis, 121 Astacobdella, 81 Asterachæres Lilljeborgii, 152 Asteromorpha lævis, 48 Atax, 136 Axinella, 66

Balanidæ on Matamata, 58 Balatro calvus, 35 Baudroie (angler), 33 Bdellura, 46 Bernard the Hermit, 23 Berne, 120 Bilharzia, 105 Birgus, 25 Black-flies, 116 Bonellia (male), 139 Bopyrus, 32, 144 Bothriocephalus latus, 105 Brachycera, 115 Bracon iniator, 168 Branchellions, 113 Bryozoa, 41 Bugs, 124 ---- of Miona, 133

Cahira lerneodiscus, 146 270 Caligi, 34, 44 ---- with cable, 72 Caligulus elegans, 73 Callianassa, 28 Cancer lanosus, 22 Cancrisocia expansa, 22 Caprella, 77 Caris elliptica, 135 Cecidomya, 171 Cellepora, 62 Cenobita, 25 Cepes distortus, 145 Ceratopogon, 119 Cercariæ, 192 Cestodes, 204 Chætogaster, 114 Chætopterus insignis, 43 Chalcididæ, 166 Chama squamata, 19 ---- Pliny on the, 18 Chelonobia, 58 Cheyletus of Leroy, 137 Chigoë, 105, 141 Chironomus, 116 Chrysaora isocela, 10 Cimex lectularia, 123 Cirrhipedes, 56 ---- on Neptunus, 59 ---- on the Langouste of Cape Verd, 58 Clione, 50 Cochlialepsis parasitus, 39 Coenurus of the Sheep, 99 Comatula, 36 Conchoderma gracile, 151 ---- on Sea Snakes, 58 Conchodytes, 17 Concholepas Peruviana, 60 Conops, 176 Corethria on Sertularia abietina, 66 Corethra, 116 Coronilla robusta, 248 Coronula, 56 Crenella on Sponge, 40, 61 Creusia, 60 Crisiæ, 61 Cryptolepas, 57 Cryptolithoides typicus, 22 Cryptophiolus minutus on Concholepas, 60 Culex pipiens, 116, 118 Cucullanus elegans, 238 Cucumerina, 71 Cuterebra noxialis, 175 Cyami, 34, 76 Cyanea arctica, 49 Cydippe densa, 47 Cylicobdella lumbricoides, 112 Cymothoa, 9 Cymothoe, 31 ---- of Trachina vipera, 32 ---- fresh-water, 32 ---- stromatei, 31 Cynips of Aphis, 172 Cypræa on Melithæa, 38 Cysticercus tenuicollis, 222 ---- of the pig, 215 ---- rabbit, 220

Demodex caninus, 134 Demodicidæ, 134 Dactylometra quinquecirra, 9 Dermanyssus avium, 135 Diadema, 56, 60 Dichelaspis on Sea Snakes, 58 Dicyema, 161 Diplozoon, 98 Diporpa, 260 Distomum filicolle, 201 ---- Goliath, 199 Distome with cables, 84 Distomes of Cheiroptera, 199 Distomidæ, 190 Distomum hepaticum, 95 ---- ocreatum, 45 ---- ventricosum, 45 Dochmius trigonocephalus, 238 Donzellina, 4 Drilus, 13 Dromia, 22

Echinococcus, 225 Echinomya, 176 Echinorhynchi, 251 Echinorhynchus angustatus, 252 ---- gigas, 96 ---- hæruca, 251 Elminius, 60 Enalcyonium rubricundum, 152 Enchelyophis vermicularis, 6 Enterocola fulgens, 151 Entoconcha, 37, 158 271 Entoniscus porcellanæ, 146 Epichtys, 31 Epibdella, 259 Epizoanthus Americanus on Eupagurus, 63 Eubranchella, 112 Eulimæ, 36 Euplectella, 23, 30, 50 Euriechinus imbecillus, 20 Eurysilenium, 152

Fabia Chilensis, 20 Fierasfer, 5 Filaria of Medina, 105, 153 ---- immitis, 153 ---- attennata, 234 Filaroides mustelarum, 250 Fishing Frog and Amphipod, 33 Fleas, 126 ---- harnessed, 129 ---- of the sea shore, 128 ---- Dugès on, 128 ---- Van Helmont on, 127 Flies, 119

Gadfly, 112 Galathea spinirostris on Comatula, 20, 61 Gammarus of Avicula, 33 Gebia, 28 Gerardia Lamarckii, 49 Glossina morsitans, 119 Gnats, 116 Gordius, 153 ---- bifurcus, 180 ---- Indian, 180 ---- ornatus, 153 Gregarinæ, 160 Guinea worm, 105, 158 Gyges branchialis, 145 Gyrodactyli, 261 Gyrodactylus elegans, 262 Gyropeltis, 74

Halichondria suberea, 63 Halodactylus, 62 Hematopinus tenuirostris, 129 Helmidasys, 47 Hemieuryale, 49 Hemioniscus, 60 Hemiptera, 262 Hemistomum alatum, 204 Heterodera Schachtii, 248 Heteroneidæ, 236 Heterosammia, 63 Heteroura androphora, 248 Hippoboscus, 175 Hirudineæ, 108 ---- of fishes, 109 ---- reptiles, 112 Histriobdella, 80 Holtenia Carpenteri, 50 Hopalocarcinus, 21 Hyalonema, 64 Hydrachna geographica, 136 Hydractiniæ, 27 Hyperinæ, 32 Hyperia Latreillii, 33 ---- galba, 33

Ichneumons, 163 Ichthyoxenus Jellinghausii, 31, 146 Iones, thoracicus, 145 Isopods, parasite, 143 Ixodes bovis, 134 ---- of the dog, 135 ---- reduvius, 134 ---- ricinus, 96, 142

Kakerlot, 23 Krätzmilben, 133

Laura, 152 Læmippa rubra, 152 Leeches, aquatic, 110 ---- land, 111 Lepidonotus cirratus, 44 Leposphilus, 147 Leptus autumnalis, 137 Leptodera, 154 ---- appendiculata, 248 ---- pellio, 248 Lernea branchialis, 151 Lerneans, 148 Lerneoniscus, 146 ---- nodicornis, 150 Lichnophora, 159 Lice of Bees, 171 Limosina, 136 Linguatula serrata, 231 Linguatulidæ, 134 Liothe pallidum, 71 272 Lithoscaspus, 21 Lipoptena of the Stag, 177 Loxostoma, 41 Lucilia hominivora, 120 Liriope, 28 Lysidice erythrocephala, 43

Macaco Worm, 175 Magilus, 39 Maia and Polypidom, 20 Malacobdella, 109 Maringouins, 116 Measled pork, 190 Meloë, 173 Meloïdeæ, 171 Melophagus of the Sheep, 177 Membranipora, 41 Mermis, 158 Messmates fixed, 53 ---- free, 4 Midges, 116 Mnemiopsis, 44 Mnestra parasites, 61 Modiola, 16 Modiolaria, 40 Monostomata, 201 Monostoma mutabile, 201 ---- bijugum, 201 ---- verrucosum, 191 Mosquitoes, 117 Musca hominivora, 119 Mutualists, 68 Myasis, 123 Myzobdella, 81 Myzostoma, 42

Nais, 114 Nebalia, 35 Nemertes carcinophilus, 46 Nemocera, 115 Nereis succinea, 42 ---- tethyeola, 43 Nirmus buteonivorus, 70 Nitzchia elegans, 259 Notonecta, 124 Notopterophorus, 151 Nycteribia, 123

Octobothrium merlangi, 261 Octocotyle lanceolata, 261 Odontobius, 45 OEga on Hyalonema, 30 OEstri, 172 Ollulanus tricuspis, 247, 250 Onchocotyle appendiculata, 261 Opalina, 79 Ophiocnemis obscura, 48 Ophioneurus, 169 Ophiothela, 48 Ornithomya, 121 Ostracion, 10 Ostracotheres tridaenæ, 17 Oxybeles lumbricoides, 7 Oxyuris brachyura, 248 ---- incurvata, 237 ---- vermicularis, 241

Pachycerca, 194 Paguri, 25 Pagurus Prideauxii, 26 Pandarus, 35 Parasites which undergo transmigration and metamorphosis, 183 ---- free in their youth, 138 ---- during their old age, 162 ---- without transmigration, 255 Pedicellina, 41, 42 Pediculinæ, 70 Peltogaster, 28, 60 Penella, 150 Pentastoma, 231 Philomedusa Vogtii on Halecampa, 61 Phoxichilidium, 35 Phthiriasis, 125 Phthirius pubis, 126 Phronima, 25 Phryxus paguri, 27, 145 ---- Rathkei, 145 Phylliroë bucephala, 61 Phyllobothrium of the Dolphin, 207 Phylloxera vastatrix, 166 Physalia, 9 Picnogonon, 34 Pilot, 10 Pinnotheres, 18 Pisa Styx, 20, 61 Piscicola, 113 Planaria, 46 273 Platygaster cyamus, 171 Platystoma, 7 Plover, Egyptian, Introd. xvi., 107 Polia involuta, 46 Polynema, 169 Polynoë, 43 Polyp of the Sterlet, 82 Polystomum integerrimum, 261 ---- ocellatum, 261 Polythoa, 64 ---- of the Adriatic, 63 Pontobdellæ, 80, 111 Pontonia, 18 Porcellanæ, 21 Porites, 62 Praniza, 75 Premnas biaculeatus, 7 Prosthetes cannelatus, 27 Protolepas, 60 Psorospermiæ, 161 Pteroptus, 123 Pulex penetrans, 141 ---- irritans, 128 Pylidium, 45 Pyrgoma, 60

Reduvius personatus, 267 Remora, 11 Rhabdites, 156 Rhagio, 119 Rhipiptera, 257 Rhincoprion penetrans, 141 Ricini, 69, 72 Rictularia plagiostoma, 251 Rouget (Cheyletus eruditus), 137

Sabelliphilus, 152 Sacculina, 59 Saphirina, 77 Sarcoptes mutans, 135 ---- scabiei, 131 Scalpellum, 56, 60 Sclerostomum equinum, 238 ---- pinguicola, 238 Scolyti, 168 Scison nebaliæ, 36 Simonea folliculi, 89, 134 Simulium molestum, 119 Siponculus concharum, 47 Sertularia parasitica, 63 Serupocellariæ, 61 Sitaris, 172 Smut in Corn, 181 Snail and Drilus, 13 Spiroptera obtusa, 246 Sphex, 170 Sphærosoma of Leydig, 74 Sphæronella Leuckarti, 151 Sphærulariæ, 235 Sphyriones, 151 Sphynx of Tithymalis, 166 Spirorbis, 44 Staurosoma on Sabella, 35 Stegophilus insidiatus, 8, 9 Sterlet, 82 Stephanurus dentatus, 238 Stratiome chameleon, 177 Strebla vespertilionis, 175 Strepsiptera, 256 Stronguli, 238 ---- of Porpoise, 239 Strongulus trigonocephalus, 240 ---- armatus, 93 ---- commutatus, 239 ---- filaria, 237 ---- gigas, 239 Stylifer, 36 Stylops, 256 Stylorhynchus oligacanthus, 161 Sylon hippolytes, 60 ---- Pandali, 60 Syngamus trachealis, 91 Syrphus, 122

Tabanus bovinus, 120 Tachinariæ, 166 Tænia coenurus, 222 ---- cucumerina, 71 ---- echinococcus, 225 ---- lata, 226 ---- magna, or Rhinoceros, 229 ---- gigantea, 229 ---- medio-canellata, 105 ---- nana, 105 ---- serrata, 71 ---- solium, 97, 105 ---- tenuicollis, 222 Temnophila, 47 Termes lucifuga, 236 Tetrarhynchus, 101 Ticks, 142 Ticks, African, 143 274 Trematoda, digenetic, 191 Trichinæ, 243 Trichiniasis, 242 Trichocera, 116 Trichocephalus affinis, 242 Trichodectes of the Dog, 70 Trichosomum crassicauda, 235, 250 Tridacna, 17 Tristoma, 259 Trombidium, 137 Tsetse, 119 Tubicinella, 34, 56 Tubularia, 84 Turtle Crab, Brown's, 23

Udonella, 44

Vaginicola, 84 Vampires, 107 Vibrio anguillula, 249

Wasps, 170 Whales of southern hemisphere, 57

Xenobalanus globicipitis, 57

Zanzare, 116 Zeuxo, 146 Zwischenwirth, 184

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By ALEXANDER BAIN, LL. D.

1 vol., 12mo. Cloth. Price, $1.50.

PROFESSOR BAIN is the author of two well-known standard works upon the Science of Mind--"The Senses and the Intellect," and "The Emotions and the Will." He is one of the highest living authorities in the school which holds that there can be no sound or valid psychology unless the mind and the body are studied, as they exist, together.

"It contains a forcible statement of the connection between mind and body, studying their subtile interworkings by the light of the most recent physiological investigations. The summary in Chapter V., of the investigations of Dr. Lionel Beale of the embodiment of the intellectual functions in the cerebral system, will be found the freshest and most interesting part of his book. Prof. Bain's own theory of the connection between the mental and the bodily part in man is stated by himself to be as follows: There is 'one substance, with two sets of properties, two sides, the physical and the mental--a _double-faced unity_.' While, in the strongest manner, asserting the union of mind with brain, he yet denies 'the association of union _in place_, but asserts the union of close succession in time,' holding that 'the same being is, by alternate fits, under extended and under unextended consciousness.'"--_Christian Register._

V.

The Study of Sociology.

By HERBERT SPENCER.

1 vol., 12mo. Cloth. Price, $1.50.

"The philosopher whose distinguished name gives weight and influence to this volume, has given in its pages some of the finest specimens of reasoning in all its forms and departments. There is a fascination in his array of facts, incidents, and opinions, which draws on the reader to ascertain his conclusions. The coolness and calmness of his treatment of acknowledged difficulties and grave objections to his theories win for him a close attention and sustained effort, on the part of the reader, to comprehend, follow, grasp, and appropriate his principles. This book, independently of its bearing upon sociology, is valuable as lucidly showing what those essential characteristics are which entitle any arrangement and connection of facts and deductions to be called a _science_."--_Episcopalian._

"This work compels admiration by the evidence which it gives of immense research, study, and observation, and is, withal, written in a popular and very pleasing style. It is a fascinating work, as well as one of deep practical thought."--_Bost. Post._

"Herbert Spencer is unquestionably the foremost living thinker in the psychological and sociological fields, and this volume is an important contribution to the science of which it treats.... It will prove more popular than any of its author's other creations, for it is more plainly addressed to the people and has a more practical and less speculative cast. It will require thought, but it is well worth thinking about."--_Albany Evening Journal._

VI.

The New Chemistry.

By JOSIAH P. COOKE, JR.,

Erving Professor of Chemistry and Mineralogy in Harvard University.

1 vol., 12mo. Cloth. Price, $2.00.

"The book of Prof. Cooke is a model of the modern popular science work. It has just the due proportion of fact, philosophy, and true romance, to make it a fascinating companion, either for the voyage or the study."--_Daily Graphic._

"This admirable monograph, by the distinguished Erving Professor of Chemistry in Harvard University, is the first American contribution to 'The International Scientific Series,' and a more attractive piece of work in the way of popular exposition upon a difficult subject has not appeared in a long time. It not only well sustains the character of the volumes with which it is associated, but its reproduction in European countries will be an honor to American science."--_New York Tribune._

"All the chemists in the country will enjoy its perusal, and many will seize upon it as a thing longed for. For, to those advanced students who have kept well abreast of the chemical tide, it offers a calm philosophy. To those others, youngest of the class, who have emerged from the schools since new methods have prevailed, it presents a generalization, drawing to its use all the data, the relations of which the newly-fledged fact-seeker may but dimly perceive without its aid.... To the old chemists, Prof. Cooke's treatise is like a message from beyond the mountain. They have heard of changes in the science; the clash of the battle of old and new theories has stirred them from afar. The tidings, too, had come that the old had given way; and little more than this they knew.... Prof. Cooke's 'New Chemistry' must do wide service in bringing to close sight the little known and the longed for.... As a philosophy it is elementary, but, as a book of science, ordinary readers will find it sufficiently advanced."-- _Utica Morning Herald._

VII.

The Conservation of Energy.

By BALFOUR STEWART, LL. D., F. R. S.

_With an Appendix treating of the Vital and Mental Applications of the Doctrine._

1 vol., 12mo. Cloth. Price, $1.50.

"The author has succeeded in presenting the facts in a clear and satisfactory manner, using simple language and copious illustration in the presentation of facts and principles, confining himself, however, to the physical aspect of the subject. In the Appendix the operation of the principles in the spheres of life and mind is supplied by the essays of Professors Le Conte and Bain."--_Ohio Farmer._

"Prof. Stewart is one of the best known teachers in Owens College in Manchester.

"The volume of THE INTERNATIONAL SCIENTIFIC SERIES now before us is an excellent illustration of the true method of teaching, and will well compare with Prof. Tyndall's charming little book in the same series on 'Forms of Water," with illustrations enough to make clear, but not to conceal his thoughts, in a style simple and brief."--_Christian Register, Boston._

"The writer has wonderful ability to compress much information into a few words. It is a rich treat to read such a book as this, when there is so much beauty and force combined with such simplicity."--_Eastern Press._

VIII.

Animal Locomotion; Or, WALKING, SWIMMING, AND FLYING.

_With a Dissertation on Aëronautics_.

By J. BELL PETTIGREW, M. D., F. R. S., F. R. S. E., F. R. C. P. E.

1 vol., 12mo. Price, $1.75.

"This work is more than a contribution to the stock of entertaining knowledge, though, if it only pleased, that would be sufficient excuse for its publication. But Dr. Pettigrew has given his time to these investigations with the ultimate purpose of solving the difficult problem of Aëronautics. To this he devotes the last fifty pages of his book. Dr. Pettigrew is confident that man will yet conquer the domain of the air."--_N. Y. Journal of Commerce._

"Most persons claim to know how to walk, but few could explain the mechanical principles involved in this most ordinary transaction, and will be surprised that the movements of bipeds and quadrupeds, the darting and rushing motion of fish, and the erratic flight of the denizens of the air, are not only anologous, but can be reduced to similar formula. The work is profusely illustrated, and, without reference to the theory it is designed to expound, will be regarded as a valuable addition to natural history."--_Omaha Republic._

IX.

Responsibility in Mental Disease.

By HENRY MAUDSLEY, M. D., Fellow of the Royal College of Physicians; Professor of Medical Jurisprudence in University College, London.

1 vol., 12mo. Cloth. Price, $1.50.

"Having lectured in a medical college on Mental Disease, this book has been a feast to us. It handles a great subject in a masterly manner, and, in our judgment, the positions taken by the author are correct and well sustained."--_Pastor and People._

"The author is at home in his subject, and presents his views in an almost singularly clear and satisfactory manner.... The volume is a valuable contribution to one of the most difficult, and at the same time one of the most important subjects of investigation at the present day."--_N. Y. Observer._

"It is a work profound and searching, and abounds in wisdom."--_Pittsburg Commercial._

"Handles the important topic with masterly power, and its suggestions are practical and of great value."--_Providence Press._

X.

The Science of Law.

By SHELDON AMOS, M. A.,

Professor of Jurisprudence in University College, London; author of "A Systematic View of the Science of Jurisprudence," "An English Code, its Difficulties and the Modes of overcoming them," etc., etc.

1 vol., 12mo. Cloth. Price, $1.75.

"The valuable series of 'International Scientific' works, prepared by eminent specialists, with the intention of popularizing information in their several branches of knowledge, has received a good accession in this compact and thoughtful volume. It is a difficult task to give the outlines of a complete theory of law in a portable volume, which he who runs may read, and probably Professor Amos himself would be the last to claim that he has perfectly succeeded in doing this. But he has certainly done much to clear the science of law from the technical obscurities which darken it to minds which have had no legal training, and to make clear to his 'lay' readers in how true and high a sense it can assert its right to be considered a science, and not a mere practice."--_The Christian Register._

"The works of Bentham and Austin are abstruse and philosophical, and Maine's require hard study and a certain amount of special training. The writers also pursue different lines of investigation, and can only be regarded as comprehensive in the departments they confined themselves to. It was left to Amos to gather up the result and present the science in its fullness. The unquestionable merits of this, his last book, are, that it contains a complete treatment of a subject which has hitherto been handled by specialists, and it opens up that subject to every inquiring mind.... To do justice to 'The Science of Law' would require a longer review than we have space for. We have read no more interesting and instructive book for some time. Its themes concern every one who renders obedience to laws, and who would have those laws the best possible. The tide of legal reform which set in fifty years ago has to sweep yet higher if the flaws in our jurisprudence are to be removed. The process of change cannot be better guided than by a well-informed public mind, and Prof. Amos has done great service in materially helping to promote this end."--_Buffalo Courier._

XI.

Animal Mechanism,

_A Treatise on Terrestrial and Aërial Locomotion_.

By E. J. MAREY,

Professor at the College of France, and Member of the Academy of Medicine.

With 117 Illustrations, drawn and engraved under the direction of the author.

1 vol., 12mo. Cloth. Price, $1.75

"We hope that, in the short glance which we have taken of some of the most important points discussed in the work before us, we have succeeded in interesting our readers sufficiently in its contents to make them curious to learn more of its subject-matter. We cordially recommend it to their attention.

"The author of the present work, it is well known, stands at the head of those physiologists who have investigated the mechanism of animal dynamics--indeed, we may almost say that he has made the subject his own. By the originality of his conceptions, the ingenuity of his constructions, the skill of his analysis, and the perseverance of his investigations, he has surpassed all others in the power of unveiling the complex and intricate movements of animated beings."--_Popular Science Monthly._

XII.

History of the Conflict between Religion and Science.

By JOHN WILLIAM DRAPER, M. D., LL. D.,

Author of "The Intellectual Development of Europe."

1 vol., 12mo. Price, $1.75.

"This little 'History' would have been a valuable contribution to literature at any time, and is, in fact, an admirable text-book upon a subject that is at present engrossing the attention of a large number of the most serious-minded people, and it is no small compliment to the sagacity of its distinguished author that he has so well gauged the requirements of the times, and so adequately met them by the preparation of this volume. It remains to be added that, while the writer has flinched from no responsibility in his statements, and has written with entire fidelity to the demands of truth and justice, there is not a word in his book that can give offense to candid and fair-minded readers."--_N. Y. Evening Post._

"The key-note to this volume is found in the antagonism between the progressive tendencies of the human mind and the pretensions of ecclesiastical authority, as developed in the history of modern science. No previous writer has treated the subject from this point of view, and the present monograph will be found to possess no less originality of conception than vigor of reasoning and wealth of erudition.... The method of Dr. Draper, in his treatment of the various questions that come up for discussion, is marked by singular impartiality as well as consummate ability. Throughout his work he maintains the position of an historian, not of an advocate. His tone is tranquil and serene, as becomes the search after truth, with no trace of the impassioned ardor of controversy. He endeavors so far to identify himself with the contending parties as to gain a clear comprehension of their motives, but, at the same time, he submits their actions to the tests of a cool and impartial examination."-- _N. Y. Tribune._

XIII.

THE DOCTRINE OF Descent, and Darwinism.

_By OSCAR SCHMIDT_,

Professor in the University of Strasburg.

WITH 26 WOODCUTS.

1 vol., 12mo. Cloth. Price, $1.50.

"The entire subject is discussed with a freshness, as well as an elaboration of detail, that renders his work interesting in a more than usual degree. The facts upon which the Darwinian theory is based are presented in an effective manner, conclusions are ably defended, and the question is treated in more compact and available style than in any other work on the same topic that has yet appeared. It is a valuable addition to the 'International Scientific Series.'"-- _Boston Post._

"The present volume is the thirteenth of the 'International Scientific Series,' and is one of the most interesting of all of them. The subject-matter is handled with a great deal of skill and earnestness, and the courage of the author in avowing his opinions is much to his credit.... This volume certainly merits a careful perusal."--_Hartford Evening Post._

"The volume which Prof. Schmidt has devoted to this theme is a valuable contribution to the Darwinian literature. Philosophical in method, and eminently candid, it shows not only the ground which Darwin had in his researches made, and conclusions reached before him to plant his theory upon, but shows, also, what that theory really is, a point upon which many good people who talk very earnestly about the matter are very imperfectly informed."--_Detroit Free Press._

XIV.

The Chemistry of Light and Photography; In its Application to Art, Science, and Industry.

_By Dr. HERMANN VOGEL_,

Professor in the Royal Industrial Academy of Berlin.

WITH 100 ILLUSTRATIONS.

12mo. Price, $2.00.

"Out of Photography has sprung a new science--the Chemistry of Light--and, in giving a popular view to the one, Dr. Vogel has presented an analysis of the principles and processes of the other. His treatise is as entertaining as it is instructive, pleasantly combining a history of the progress and practice of photography--from the first rough experiments of Wedgwood and Davy with sensitized paper, in 1802, down to the latest improvements of the art--with technical illustrations of the scientific theories on which the art is based. It is the first attempt in any manual of photography to set forth adequately the just claims of the invention, both from an artistic and a scientific point of view, and it must be conceded that the effort has been ably conducted."--_Chicago Tribune._

XV.

Fungi; THEIR NATURE, INFLUENCE, AND USES.

_By M. C. COOKE, M. A., LL. D._

Edited by Rev. M. J. BERKELEY, M. A., F. L. S.

With 109 Illustrations. Price, $1.50.

"Even if the name of the author of this work were not deservedly eminent, that of the editor, who has long stood at the head of the British fungologists, would be a sufficient voucher for the accuracy of one of the best botanical monographs ever issued from the press.... The structure, germination, and growth of all these widely-diffused organisms, their habitats and influences for good and evil, are systematically described."--_New York World._

"Dr. Cooke's book contains an admirable _résumé_ of what is known on the structure, growth, and reproduction of fungi, together with ample bibliographical references to original sources of information."--_London Athenæum._

"The production of a work like the one now under review represents a large amount of laborious, difficult, and critical work, and one in which a serious slip or fatal error would be one of the easiest matters possible, but, as far as we are able to judge, the new hand-book seems in every way well suited to the requirements of all beginners in the difficult and involved study of fungology."--_The Gardener's Chronicle (London)._

XVI.

The Life and Growth of Language: AN OUTLINE OF LINGUISTIC SCIENCE.

_By WILLIAM DWIGHT WHITNEY_,

Professor of Sanskrit and Comparative Philology in Yale College.

1 vol., 12mo. Cloth. Price, $1.50.

"Prof. Whitney is to be commended for giving to the public the results of his ripe scholarship and unusually profound researches in simple language. He draws illustrations and examples of the principles which he wishes to impact, from common life and the words in frequent use.

"The topics discussed in this volume are, for the most part, those which have been already treated by other writers on philology, and even by the author himself, in his volume on 'Language, and the Study of Language,' published a few years ago, and, though many of the truths here set forth are those with which students in the same line of investigation are generally familiar, all will rejoice to see them restated in such a fresh and simple way.

"This work, while valuable to scholars, will be interesting to every one."--_The Churchman._

"This work is an important contribution to a science which has advanced steadily under conditions that appear constantly to throw an increasing light on difficult questions, and at each step clear the way for further discoveries."--_Chicago Inter-Ocean._

"Prof. Whitney is undoubtedly one of the foremost of English-speaking philologists, and occupies an enviable position in the wider circle of European students of language.

"His style, clear, simple, picturesque, abounding in striking illustrations, and apt in comparisons, is admirably fitted to be the vehicle of a popular treatise like the work under consideration."-- _Portland Daily Press._

XVII.

Money and the Mechanism of Exchange.

_By W. STANLEY JEVONS, M. A., F. R. S._,

Professor of Logic and Political Economy in the Owens College, Manchester.

1 vol., 12mo. Cloth. Price, $1.75.

"He offers us what a clear-sighted, cool-headed, scientific student has to say on the nature, properties, and natural laws of money, without regard to local interests or national bias. His work is popularly written, and every page is replete with solid instruction of a kind that is just now lamentably needed by multitudes of our people who are victimized by the grossest fallacies."--_Popular Science Monthly._

"If Professor Jevons's book is read as extensively as it deserves to be, we shall have sounder views on the use and abuse of money, and more correct ideas on what a circulating medium really means."-- _Boston Saturday Evening Gazette._

"Professor Jevons writes in a sprightly but colorless style, without trace of either prejudice or mannerism, and shows no commitment to any theory. The time is not very far distant, we hope, when legislators will cease attempting to legislate upon money before they know what money is, and, as a possible help toward such a change, Professor Jevons deserves the credit of having made a useful contribution to a department of study long too much neglected, but of late years, we are gratified to say, becoming less so."--_The Financier, New York._

XVIII.

The Nature of Light, WITH A GENERAL ACCOUNT OF PHYSICAL OPTICS.

_By Dr. EUGENE LOMMEL_

(University of Erlangen).

1 vol., 12mo. Cloth. Price, $2.00.

"In the present treatise, Professor Lommel has given an admirable outline of the nature of light and the laws of optics.

"Unlike most other writers on this subject, the author has, we think, wisely postponed all reference to theories of the nature of light, until the laws of reflection, refraction, and absorption, have been clearly set before the reader. Then, in the fifteenth chapter, Professor Lommel discusses Fresnel's famous interference experiment, and leads the reader to see that the undulatory theory is the only conclusion that can be satisfactorily arrived at. A clear exposition is now given of Huyghen's theory, after which follow several chapters on the diffraction and polarization of light-bearing waves.

"The reader is thus led onward much in the same way as the science itself has unfolded, and this, we think, is the surest and best way of teaching natural knowledge.

"We have said enough to show that Professor Lommel's treatise is a useful contribution to the 'International Series'--a book that can thoroughly be understood and enjoyed by any intelligent reader who may not have had any special scientific training."--_Nature._

"In a style singularly lucid, considering the abstruse nature of the subject treated, Dr. Lommel unfolds the learning of the scientists on the nature and phenomena of light."--_Philadelphia Inquirer._

"As a popular introduction to physical optics, it would be difficult to find a more satisfactory work than the one by Dr. Lommel, which has just appeared in the excellent 'International Scientific Series.'"--_The English Mechanic._

D. APPLETON & CO., PUBLISHERS, 549 & 551 Broadway, N. Y.

THE INTERNATIONAL SCIENTIFIC SERIES.

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The character and scope of this series will be best indicated by a reference to the names and subjects included in the subjoined list, from which it will be seen that the coöperation of the most distinguished professors in England, Germany, France, and the United States, has been secured, and negotiations are pending for contributions from other eminent scientific writers.

The works will be issued in New York, London, Paris, Leipsic, Milan, and St. Petersburg.

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Prof. W. KINGDON CLIFFORD, M. A. _The First Principles of the Exact Sciences explained to the Non-mathematical._

Prof. T. H. HUXLEY, LL. D., F. R. S. _Bodily Motion and Consciousness._

Dr. W. B. CARPENTER, LL. D., F. R. S. _The Physical Geography of the Sea._

Prof. WILLIAM ODLING, F. R. S. _The Old Chemistry viewed from the New Stand-point._

W. LAUDER LINDSAY, M. D., F. R. S. E. _Mind in the Lower Animals._

Sir JOHN LUBBOCK, Bart., F. R. S. _On Ants and Bees._

Prof. W. T. THISELTON DYER, B. A., B. Sc. _Form and Habit in Flowering Plants._

Mr. J. N. LOCKYER, F. R. S. _Spectrum Analysis._

Prof. MICHAEL FOSTER, M. D. _Protoplasm and the Cell Theory._

H. CHARLTON BASTIAN, M. D., F. R. S. _The Brain as an Organ of Mind._

Prof. A. C. RAMSAY, LL. D., F. R. S. _Earth Sculpture: Hills, Valleys, Mountains, Plains, Rivers, Lakes; How they were Produced, and how they have been Destroyed._

Prof. RUDOLPH VIRCHOW (Berlin University). _Morbid Physiological Action._

Prof. CLAUDE BERNARD. _History of the Theories of Life._

Prof. SAINTE-CLAIRE DEVILLE. _An Introduction to General Chemistry._

Prof. WURTZ. _Atoms and the Atomic Theory._

Prof. De QUATREFAGES. _The Human Race._

Prof. LACAZE-DUTHIERS. _Zoölogy since Cuvier._

Prof. BERTHELOT. _Chemical Synthesis._

Prof. C. A. YOUNG, Ph. D. (of Dartmouth College). _The Sun._

Prof. OGDEN N. ROOD (Columbia College, N. Y.). _Modern Chromatics and its Relations to Art and Industry._

Dr. EUGENE LOMMEL (University of Erlangen). _The Nature of Light._

Prof. J. ROSENTHAL. _General Physiology of Muscles and Nerves._

Prof. JAMES D. DANA, M. A., LL. D. _On Cephalization; or, Head-characters in the Gradation and Progress of Life._

Prof. S. W. JOHNSON, M. A. _On the Nutrition of Plants._

Prof. AUSTIN FLINT, Jr., M. D. _The Nervous System, and its Relation to the Bodily Functions._

Prof. BERNSTEIN (University of Halle). _The Five Senses of Man._

Prof. FERDINAND COHN (Breslau University). _Thallophytes (Algæ, Lichens, Fungi)._

Prof. HERMANN (University of Zurich). _Respiration._

Prof. LEUCKART (University of Leipsic). _Outlines of Animal Organization._

Prof. LIEBREICH (University of Berlin). _Outlines of Toxicology._

Prof. KUNDT (University of Strasburg). _On Sound._

Prof. REES (University of Erlangen). _On Parasitic Plants._

Prof. STEINTHAL (University of Berlin). _Outlines of the Science of Language._

P. BERT (Professor of Physiology, Paris). _Forms of Life and other Cosmical Conditions._

E. ALGLAVE (Professor of Constitutional and Administrative Law at Douai, and of Political Economy at Lille). _The Primitive Elements of Political Constitutions._

P. LORAIN (Professor of Medicine, Paris). _Modern Epidemics._

Prof. SCHUTZENBERGER (Director of the Chemical Laboratory at the Sorbonne). _On Fermentations._

Mons. FREIDEL. _The Functions of Organic Chemistry._

Mons. DEBRAY. _Precious Metals._

Prof. CORFIELD, M. A., M. D. (Oxon.). _Air in its Relation to Health._

Prof. A. GIARD. _General Embryology._

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Transcriber's Note

Variant and obsolete spellings were not changed. Footnotes were renumbered sequentially and moved to the end of the chapter in which the related anchor occurs. Illustrations that fell within paragraphs were moved to precede or follow the paragraph, and in some cases no longer occur on the page number listed in the List of Illustrations. Words in italics are surrounded by underscores, _like this_. A few index entries are not listed in alphabetical order.

Alterations:

Deleted duplicate words: Page 24 - 'and and' ... bottom of the sea, and in which ... Page 24 - 'the the' ... march boldly on the enemy,... Page 185 - 'of of' ... The stomach of the carnivorous animal ... Added: Missing periods, quote marks, and commas to sentences, illustrations and index entries. 'F' to 'IXED' in Table of Contents for Chapter 3. Second 'as' to '... it attacks great as well as little ...' Page number to index entry for Apterychtus ocellatus Changed: List of illustrations - page number from 226 to 227 for Figure 58 Page xviii - 'villany' to 'villainy' ... or by superior villainy ... Page xviii - 'copepode' to 'copepod' ... a copepod crustacean ... Page xviii - 'rack' to 'back' ... by keeping his back clean,... Page 12 - 'Psclaphidæ' to 'Pselaphidæ' Page 23 - 'ascercertain' to 'ascertain' ...difficult to ascertain;... Page 31 - 'Blecker' to 'Bleeker' ... Dr. Bleeker, who has so ... Page 105 - 'pecular' to 'peculiar' ... their peculiar host ... Page 146 - 'Ichthoxenus' to 'Ichthyoxenus' ...Ichthyoxenus Jellinghausii... Page 251 - 'remakable' to 'remarkable' ... very remarkable group ... Page 215 - comma to period ... to injured corn and mouldy bread. Fig. 66 - periods to commas after numbers 2 & 3 in caption Page 242 - period to comma ... on this subject, in which he said ... Page 244 - comma to period ...their true nature. He referred ... Page 248 - 'Shachti' to 'Schachtii' ... _Heterodera Schachtii_ ... Index - 'Ichthoxenus Jellingshausii' to 'Ichthyoxenus Jellinghausii'