Part 46

It may be reasonably objected that the most elementary facts concerning the development of teeth prove that their shapes cannot be altered during the lifetime of the individual, except by being worn away. The shape is predetermined before the tooth has cut the gum. Hence the Neo-Lamarckian School assumes, not the transmission of acquired characters, but the transmission of characters which the parent is unable to acquire!—E. B. P.]

Footnote 297:

See p. 412 of the preceding Essay (VII).

Footnote 298:

[See ‘Nature,’ vol. xxix. p. 20, and vol. xxxv. p. 38. In the latter article nine generations are recorded, and in both articles figures of the normal and abnormal feet are given. Additional generations and many more families have been since observed, and an account of these observations will shortly be published in the same paper. The breed originally came from Bristol. In the observations recorded, the abnormality of the offspring is an indication of the hereditary strength of the female parents, while the degree of normality is a similar test of heredity through the male parents; for the female parents were always abnormal, the male parents always normal. The most abnormal kitten observed possessed seven toes on each forefoot, seven toes on the right hind foot (three more than the normal number), and six on the left hind foot. Kittens with seven toes on the forefeet and six on the hind were comparatively common, and all intermediate conditions between this and the normal were of frequent occurrence. Cats with extra toes are, I think, not uncommon in most countries, and the fact that the peculiarity is transmitted is also well known. The object of the investigation alluded to was to observe the transmission systematically through many generations.—E. B. P.]

Footnote 299:

Bonnet, ‘Die stummelschwänzigen Hunde im Hinblick auf die Vererbung erworbener Eigenschaften,’ Anat. Anzeiger, Bd. III, 1888, p. 584; see also ‘Beiträge zur patholog. Anatomie und allgem. Pathologie’ by Ziegler and Nauwerck, Bd. IV, 1888.

Footnote 300:

See the interesting remarks by Döderlein on this point, which Dr. Ischikawa of Japan tells me are quite correct. Döderlein, ‘Ueber schwanzlose Katzen,’ Zool. Anzeiger, vol. x. Nov. 1887, No. 265.

Footnote 301:

It is certainly true that among nations which practise circumcision as a ritual, children are sometimes born with a rudimentary prepuce, but this does not occur more frequently than in other nations in which circumcision is not performed. Rather extensive statistical investigations have led to this result.

Footnote 302:

See Brock, ‘Biolog. Centralblatt,’ Bd. VIII. p. 497, 1888.

Footnote 303:

W. Richter, ‘Zur Vererbung erworbener Charaktere,’ Biolog. Centralblatt, Bd. VIII. 1888, p. 289.

Footnote 304:

This case was not observed by Darwin himself, but was communicated to him by J. P. Bishop of Perry, in North America (see ‘Kosmos,’ vol. ix. p. 458). Quite apart from the fact that it is by no means certain whether the father did not already possess an innate malformation of the thumb, exact data are wanting as to the time during which the thumb was diseased, and as to the time when the malformation of the thumb was first observed in the children and the grandchildren; whether at birth or at a later period. For a thorough criticism it would also be necessary to have figures of the thumbs. I should not have alluded to this case, because of its incomplete history, if it had not appeared to me to illustrate the ideas mentioned above. Of course I do not maintain that I have suggested the right explanation in this particular case. It is possible that the father possessed an inherent malformation of the thumb which he had forgotten by the time that he came to have children and grandchildren, and was struck by the abnormality of their thumbs.

Footnote 305:

See Burdach, ‘Lehrbuch der Physiologie,’ Bd. II, 1835-40, p. 128.

Footnote 306:

See Handwörterbuch der Physiologie von Rud. Wagner, Artikel ‘Zeugung,’ von Rud. Leuckart.

Footnote 307:

See V. Hensen, ‘Physiologie der Zeugung.’ Leipzig, 1881.

INDEX.

Abutilon, polymorphic flowers of, pp. 320, 323. Acanthia lectularia, length of life of, 42. Acineta, 151. Acquired characters, meaning of, 169; on supposed botanical proofs of transmission of, 390, 397. Acridium migratorium, length of life of, 40. Actinia mesembryanthemum, length of life of, 54. Actinosphaerium, 117, 118. Activity and length of life, 7, 8. Adansonia, length of life of, 6. Adler, on the formation of galls, 302. After-effects, 403. Aglia tau, deposition of eggs, 18; length of life of, 18, 59. Algae, immortality of unicellular, 25. Amoeba, length of time of fission of, 8; immortality of, 25; fission of, 25, 64. Amphibia, polar bodies of, 340, 352. Amphileptus meleagris, fission of, 148. Amphorina coerulea, polar bodies of, 189. Anabiosis, 25, 38. Ancylus, length of life of, 56. Andricus, length of life of summer generation, 50. Anisotropism, 400. Anlagen, 192. Anodonta, length of life of, 56, 57. Ants, duration of life of male and female, 18, 48, 50, 51, 52, 59, 156. Aphilotrix, length of life of imago of, 50. Aphis, length of life of, 41; parthenogenesis of, 228, 289; polar bodies of, 349. Apis, _see_ Bees. Apus, 152, 324. Ascaris, 133, 144; fertilization of, 177; nuclear division in ovum of, 188, 232, 360; spermatogonia of, 220; spermatogenesis of, 375. Ascidians, length of life of, 57. Atavism, 179. Atrophy, of organs, 85, 86. Auerbach, on fertilization, 355.

Bacteria, in dead Cockchafer, 46. Baer, von, 194; on the influence of maternal impressions on the offspring, 445. Balanus, polar bodies of, 218. Balbiani, on nuclear division, 187; on pole-cells, 197; on origin of ova, 222. Balfour, on impregnation, 175; on polar bodies, 214, 225, 339, 345, 353. Bear, length of life of, 13. Bees, length of larval life of, 15; length of life of queen of, 18, 52, 156; of drones, 18, 53; of workers, 52, 59, 156; activity of, 48; oviposition of, 52, 54; death of male, 63, 120, 132; loss of limbs in development of larva, 89; nuptial flight of, 93; development of eggs of, 226, 234, 285, 351. Begonia, propagation of, 211. Beneden, van, on fertilization in Ascaris, 177, 188, 355, 360; on polar bodies, 214, 340, 345, 353; on Polkörperchen, 216; on spermatogonia in Ascaris, 220, 375; on nuclear division, 231; on sexual reproduction, 282. Berthold, on male parthenogenesis, 247. Bessels, on importance of fertilization, 235. Beyerinck, on the formation of galls, 302. Biorhiza, length of life of imago of, 50. Birds, length of life of, 11, 36; factors in duration of life of, 12. Blackbird, length of life of, 6, 11, 36. Blaps, length of life of imago of, 47, 48. Blastogenic characters, 412. Blochmann, on polar bodies, 349. Blow-flies, length of larval life of, 15. Boar, length of life of, 14. Bombinator igneus, nature of ovum of, 125. Bombus, 53. Bombyces, flight of females impeded by eggs, 17; habits of, 44. Bonellia viridis, unequal length of life of male and female, 59. Bonnet, on rudimentary tails in dogs, 428. Born, on position of nucleus in ova, 177; on double impregnation, 382. Bosmina, parthogenesis of, 325. Brooks, on heredity, 166, 326. Brown-Séquard, experiments on guinea-pigs, 81, 310, 313. Bulimus, length of life of, 55. Buprestis splendens, length of life of, 47. Burdach, on the influence of maternal impressions on the offspring, 444. Bütschli, on polar bodies, 188, 214, 224, 340; on sexual reproduction, 282; on processes of fertilization, 355. Butterflies, climatic varieties of, 99; death of, 120. Bythotrephes, spermatozoa of, 176; summer eggs of, 239; winter eggs of, 348.

Calberla, on impregnation in Petromyzon, 175. Canary birds, length of life of, 36; plumage of, 321. Carabus auratus, length of life of imago of, 47. Carnoy, on karyokinesis in ovum of Ascaris, 360, 368; on spermatogenesis, 375. Carp, length of life of, 6. Cat, length of life of, 6. Catallacta, 123. Caterpillars, length of life of phytophagous, 15. Cells, renewal of, 21; nourishment of, 29; death of, 59. Cephalopods, length of life of, 56. Cerambyx heros, length of life of imago of, 47. Cetochilus, polar bodies of, 218. Chermes, parthogenesis of, 294; galls of, 401. Cherry-tree, in Ceylon, 406. Chrysomela varians, ovoviviparous development of, 48, 49. Chydorus, parthenogenesis of, 325. Cicada, length of life of, 41, 42. Cienkowsky, on conjugation, 286. Cionea intestinalis, length of life of, 57. Circumcision, 434. Cirrhipedes, complementary males of, 58. Clausilia, length of life of, 55. Cockchafer, length of larval life of, 16; length of imaginal life of, 46. Coleoptera, length of life of, 46. Colpoda cucullus, fission of, 148. Conjugation, 282, 286. Continuity of germ-plasm, 104. Copepods, unequal length of life in the two sexes of parasitic, 58. Coryne, origin of sexual bud, 205. Cossus ligniperda, length of larval life of, 15. Crayfish, length of life of, 6. Cuckoo, length of life of, 11, 36. Cyclas, length of life of, 56. Cynipidae, length of life of, 49; number of eggs of agamic, 50; deposition of eggs of, 93; number of males of, 293. Cynips, amount of nuclear matter in egg of, 229; parthenogenesis of, 274, 290, 293. Cypris, 294. Cyto-idioplasm, 181, 184. Cytoplasm, 184.

Daphnidae, segmentation of the egg of, 73, 199; loss of jaws in development of, 89; winter eggs of, 121; sperm cells of, 175, 176; parthenogenesis of, 228, 325; summer eggs of, 236, 239, 240; polar bodies in parthenogenetic eggs of, 249, 345, 350. Darwin, on constancy of number of individuals in successive generations, 12; on Pangenesis, 77, 370; on atrophy of organs, 85, 90; on cross fertilization, 309; on effect of external influences, 391, 423. Daucus, structure of root altered by cultivation, 414. Death, origin of, 20, 21, 143; relation to reproduction, 21, 120, 132, 154; necessity of, 23, 24, 134, 159; utility of, 24, 112, 135, 153; an adaptation produced by natural selection, 24, 28, 60; not universal, 25, 27, 111, 119; by sudden shock, 63; meaning of, 113; definition of, 114; of the soma, 154. Degeneration of organs, _see_ Atrophy. Detmer, on transmission of acquired characters in plants, 390. Development amongst Protozoa, 149. Diatomaceae, fission of, 65. Dicyemids, 131, 141. Diptera, length of life of, 42; pole cells of, 197, 206, 210, 216; as fertilizers of flowers, 309. Döderlein, on tailless cats, 390, 428, 430. Dragon-flies, length of larval life of, 15; length of life of imago, 17, 40. Dryophanta, length of life of summer generation of, 49; of winter generation, 50. du Bois Reymond, on the transmission of acquired characters, 82, 390, 422. Duration of life governed by needs of species, 9. Düsing, on origin of sex, 239, 241.

Eagles, length of life of, 11, 37; weight of, 14. Echinodermata, origin of germ-cells, 202. Echinus, polar bodies of, 351. Ectocarpus, male parthenogenesis in, 247. Eggs, number laid by various birds, 12, 37; of insects, 17. Eider-ducks, length of life of, 11. Eimer, on the inheritance of mutilations, 426. Eleodes grandis, and dentiper, length of life of imago of, 47. Elephants, length of life of, 6; gestation of, 7. Encystment, relation to death of, 112, 115, 116, 120, 158; protective, 117, 121; of Rhizopoda, 121. Entoniscidae, unequal length of life in male and female, 58. Ephemeridae, length of life of imago of, 40, 156. Epigenesis, theory of, 316. Eristalis tenax, length of life of, 43. Estheridae, 228. Euglypha, identity of products of fission of, 26, 64, 65. Eupithecia, length of life of, 45.

Falcons, length of life of, 11, 37. Fiedler, on polar bodies in sponges, 217. Flemming, on nuclear division, 187, 231, 359, 361. Flourens, on length of life, 7. Fol, on fusion of nuclei, 174, 189; on origin of ova, 222; on multiple impregnation, 236, 238, 382; on polar bodies, 340, 351; on process of fertilization, 355. Formica sanguinea and fusca, length of life of, 51. Fox, length of life of, 14.

Galls, 302, 401. Galton, on transfusion in Rabbits, 166; on heredity, 172; on twins, 380. Gannets, numbers collected each year, 37. Geotropism, 398. Germ, meaning of, 148. Germ-cells, 73; predisposition of the, 84, 102; fluctuations in, 102; not continuous, 173. Germ-plasm, 80, 191, 266, 341, 357, 371, 403; continuity of, 104, 168, 173, 184; definition of, 174. Goliathus cacicus, length of life of imago of, 47. Goose, length of life of the wild, 37. Götte, on necessity of death, 112; on rejuvenescence, 115, 124; on death of Metazoa, 125. Gregarines, 148, 149, 202. Grobben, on polar bodies of Cetochilus, 218. Gruber, on regeneration amongst Infusoria, 185. Gryllotalpa, duration of life of, 39. Gryllus campestris, duration of life of, 39.

Häckel, on reproduction, 72; on Perigenesis of the Plastidule, 165; on amphigonic reproduction, 272. Hare, length of life of, 14. Hartlaub, on origin of germ-cells in Obelia, 208. Hawk-moths, length of life of imago, 17. Helicidae, length of life of, 55, 56, 57. Heliotropism, 399. Hemiptera, length of life of, 41. Hens, length of life of, 36. Hensen, on sexual reproduction, 282, 286; on difference between germ-plasm and histogenetic nucleoplasm, 343; on heredity, 369. Heredity, 29, 71, 378; defined, 72; dependent on continuity of germ-plasm, 104, 168; dependent on coalescence of nuclei, 178. Hertwig, O., on fusion of nuclei, 174; on the influence of gravity in segmentation, 177, 189; on polar bodies, 340, 351; on process of fertilization, 355. Hesperornis, rudimentary wing of, 88. Heterogeny, 325. Heterogynis, 44. Heteroplastides, 130, 131, 134, 139, 146, 153, 204. Hildebrandt, on duration of life in plants, 32, 65; on cross-fertilization, 309. His, on heredity, 166, 390, 412; on the transmission of mutilations, 423. Hoek, on polar bodies in Balanus, 218. Hoffman, on transmission of acquired characters, 407. Homoplastides, 122, 139, 146, 202. Horse, length of life of, 6, 7; in the Falkland Islands, 99. Humboldt’s Atur Parrot, 12. Hunter, John, experiments in Anabiosis, 25. Hyalineae, length of life of, 56. Hybrids, 330. Hydroids, origin of germ-cells of, 199, 206, 207, 211. Hyla, 301, 394. Hymenoptera, length of life of, 49. Hypermetropia, 89.

Ichneumons, length of larval life of, 15; length of life of imago of, 49. Ichthyophthirius multifiliis, fission of, 148, 149. Idioplasm, 174, 184, 192, 341; not identical with nucleoplasm, 180; relation to chromatin, 217; two kinds of, 245; various combinations of, 276. Imago, length of life of, 16. Immortality, injurious to species, 24; of unicellular organisms, 25, 27, 33. Infusoria, immortality of, 25, 72; regeneration of lost parts in, 27, 185; fission of, 64; encystment of, 117. Insects, duration of life amongst, 15; duration of larval life of, 15; normal death of, 22; duration of imaginal life of, 38; segmentation of egg of, 73; deposition of eggs, 93; origin of germ-cells of, 202; polar bodies of, 218. Instinct, 83; origin of, 91, 389; used but once in a lifetime, 93. Isotropism, of the ovum, 176. Ivy, climbing shoots of, 393, 399.

Jäger, on heredity, 172, 206. Jordan, on varieties, 269. Julin, on spermatogenesis in Ascaris, 375.

Kallima, mimicry of, 280, 306. Kant, on the transmission of mutilations, 423. Karyokinesis, 359, 375. Keim, _see_ Germ. Kirchner, on development of Volvox, 204. Kölliker, on nature of spermatozoa, 175; on embryonic cells, 196.

Lagynus, fission of, 148. Lamarck, on use and disuse, 83, 84, 303, 387, 391, 421. Lamellibranchiata, length of life of, 55. Larvae, length of life of, 15. Lasius flavus, length of life of, 50; L. niger, 51. Lepidoptera, length of life of imagos of, 43, 156; parthenogenesis among, 226, 352; spermatogenesis in, 375. Lepisma saccharina, length of life of, 40. Leuckart, on relation of absorbing surface to size of animal, 7; on development of Bees, 235; on the influence of maternal impressions on the offspring, 445. Limnadia Hermanni, 152. Limnaeus, length of life of, 56. Lion, length of life of, 13. Lister, on chromatophores of blind Frogs, 301. Locusta, length of life of imago of, 39. Lotze, on activity in connection with longevity, 7. Lucanus cervus, length of life of imago of, 47. Lycaena violacea, length of life of imago of, 44. Lynceinae, spermatazoa of, 176.

Macroglossa stellatarum, length of life of female of, 45. Magosphaera planula, 75, 120, 122, 126, 147, 152; figure of, 123. Magpies, length of life of, 36. Mammals, duration of life of, 38. Manx cats, 427, 430. Maternal impressions, supposed influence on offspring, 444. May-flies, length of larval life of, 15; length of life of imago of, 16; habitat of larvae of, 17; shortening of life of, 19; death of, 120. Meldola, 395. Melolontha vulgaris, _see_ Cockchafer. Mesozoa, 128. Metazoa, 27, 28, 111, 145; old age of, 157. Metschnikoff, on pole-cells, 197. Micellae, 190, 194. Mimetic forms, 264, 280. Mimosa, ‘after effects’ in, 404. Minot, on cyclical development, 199; on polar bodies, 214, 225, 340, 345, 353. Moina, winter eggs of, 118, 240; segmentation of, 199; polar bodies of, 218. Molluscs, length of life of, 55; determined by markings on shell, 14; enemies of, 58. Monoplastides, 115, 122, 125, 146, 159; definition of, 120; reproduction of, 149. Mouse, length of life of, 6; gestation of, 7. Müller, F., on heredity of acquired characters, 320, 322. Müller, H., on colours of flowers, 259; on nectaries, 307. Multicellular organisms, division of labour in, 27. Musca domestica, length of life of, 43. Musca vomitoria, polar bodies of, 353. Myopia, 89.

Nägeli, 167, 171, 175; on idioplasm, 174, 182, 190, 201, 340, 414; on inherent tendency to vary, 256, 298; on Alpine plants, 269; on adaptation, 300; on medium of heredity, 318, 355. Najadae, length of life of, 56. Natica heros, length of life of, 56. Nautilus, persistence of, 300. Nematodes, polar bodies of, 188; nuclear division of ovum of, 234, 368. Neuroptera, length of life of, 40. Neuroterus, length of life of summer generation, 49; of winter generation, 50. Nigella, production of double flowers of, 408. Nightingale, length of life of, 11, 36. Nothnagel, on the cause of epilepsy, 314. Nuclear plate, 187. Nuclei, behaviour during fission, 118, 188; connection of heredity with fusion of, 178; influence of, 184; influence in regeneration, 185; nutrition of, 187. Nucleoplasm, 179, 185, 191, 227; histogenetic, 213; ovogenetic, 213, 230, 243; spermogenetic, 220, 243. Nussbaum, on heredity, 172, 195, 206; on regeneration amongst Infusoria, 185, 200.

Obelia, origin of germ-cells of, 208. Obersteiner, on inheritance of epilepsy in guinea pigs, 311, 313. Ophiostomum, karyokinesis in ovum of, 368. Orgyia, 44. Orth, on the transmission of acquired characters, 411. Orthonectides, 120, 126; figure of, 127; degeneracy of, 130, 131, 141, 152. Orthoptera, duration of life of, 39. Ostracodes, parthenogenesis of, 294, 325; polar bodies of, 350. Otostoma Carteri, fission of, 148.

Palingenia, sub-imago stage of, 19, 40. Paludinidae, length of life of, 56. Pandorina, 202, 248; figure of, 203. Pangenesis, theory of, 77, 165, 166, 193, 316, 327. Panmixia, principle of, 90, 140, 291, 430. Papaver, production of double flowers of, 408. Paranucleus, 376; of the sperm-cell, 221. Parrots, length of life of, 36. Parthenogenesis, the origin of, 225, 290, 323, 339; not ancestral, 228; of bees, 235; partial, 238; explanation of, 243; male, 247; of Cynips, 273; not perpetual, 283, 285. Pasimachus, length of life of, 48. Pemphigus terebinthi, length of life of, 41. Petromyzon, impregnation of, 175, 247; polar bodies of, 218. Pfeffer, on chemical attraction of oosphere, 247. Pfitzner, on nuclear division, 187. Pflüger, on heredity, 70, 175, 355; on the inheritance of acquired characters, 81, 390, 422; on isotropism of the ovum, 176. Phanerogams, fertilization of, 178, 247; development of pollen grains of, 222. Pheasant, the length of life of the golden, 36. Philodina, polar bodies of, 350. Phryganea grandis, 41. Phylloxera vastatrix, length of life of, 41; unequal length of life in two sexes of, 58; parthenogenesis of, 294. Pieris napi, length of life of, 44. Pig, length of life of, 6. Pigeon, length of life of, 36; cross-breeding of, 332. Pike, length of life of, 6. Pisidium, length of life of, 56. Planorbis, length of life of, 56. Plants, duration of life of, 32, 65. Polar bodies, 188, 218, 245; the significance of, 212, 225, 339; of Sponges, 217; in parthenogenetic eggs, 249, 345, 383; of Rabbit, 339; number of, 346; significance of second, 353, 362; in plants, 377. Pole-cells, of Diptera, 197. Polistes gallica, ‘workers’ of, 53; length of life of males and females, 54. Pollen-grains, 222. Polyphemus, spermatozoa of, 176; summer eggs of, 239; polar bodies of, 345. Polyplastides, definition of, 120, 122, 125, 159; development of, 152. Polyzoa, length of life of, 57. Poulton, on colours of caterpillars, 394; on cats with supernumerary toes, 426. Proteus, 87. Protomyxa aurantiaca, 149. Protozoa, development amongst, 150; conjugation of, 287. Psorosperms, 150. Psychidae, length of life of, 16, 44, 45, 157; deposition of eggs of, 18; death of female, 63, 132; parthenogenesis of, 293. Pulex irritans, length of life of, 42. Pupa, length of life of, 55.

Rabbit, polar bodies of, 339. Rauber, on heredity, 172. Ravens, length of life of, 36. Regeneration of lost parts, 65; in Infusoria, 185. Rejuvenescence, 112, 116, 124, 132, 153, 283. Reproduction, original form of, 122; effect of monogonic, 273, 275; amphigonic, 279, 281, 287. Reproductive cells, 27, 28, 111. Rhodites rosae, parthenogenesis of, 325. Richter, on inheritance of acquired characters, 438. Robin, on pole-cells of Diptera, 197. Rolph, on conjugation, 286. Romanes, on correlation, 389. Roth, on heredity, 166, 169. Rotifera, unequal length of life in two sexes of, 58; polar bodies of, 350. Roule, on origin of ova, 222. Roux, on the struggle of the parts in the organism, 87, 100; on development in altered conditions, 177; on forces controlling nuclear division, 231, 361; on karyokinesis, 359. Rudimentary organs, 88; disappearance of, 291; not found in parthenogenetic forms, 293. Rumia Crataegata, 394.