Chapter 10

The red spider is not correctly speaking an insect, though it is commonly spoken of as such, neither is it a spider, as its name would imply, but an acarus or mite. Whether its name is correct or not, it is a most destructive and troublesome pest wherever it makes its presence felt, it by no means confines itself to one or only a few kinds of plants, as many insects do, but it is very indiscriminate in its choice of food, and it attacks both plants grown under glass and those in the open air. When these pests are present in large numbers, the leaves on which they feed soon present a sickly yellow or scorched appearance, for the supply of sap is drawn off by myriads of these little mites, which congregate on the under sides of the leaves, where they live in a very delicate web, which they spin, and multiply very rapidly; this web and the excrement of the red spider soon choke up the pores of the leaves, which, deprived of their proper amount of sap, and unable to procure the carbon from the atmosphere which they so much need, are soon in a sorry plight. However promiscuous these mites may be in their choice of food plants--melons, cucumbers, kidney beans, hops, vines, apple, pear, plum, peach trees, limes, roses, laurustinus, cactuses, clover, ferns, orchids, and various stove and greenhouse plants being their particular favorites--they are by no means insensible to the difference between dryness and moisture. To the latter they have a most decided objection, and it is only in warm and dry situations that they give much trouble, and it is nearly always in dry seasons that plants, etc., out of doors suffer most from these pests. Fruit trees grown against walls are particularly liable to be attacked, since from their position the air round them is generally warm and dry, and the cracks and boles in the walls are favorite places for the red spider to shelter in, so that extra care should be taken to prevent them from being infested, this may best be effected by syringing the trees well night and morning with plain water, directing the water particularly to the under sides of the leaves, so as, if possible, to wash off the spiders and their webs. If the trees be already attacked, adding soft soap and sulphur to the water will destroy them.

Sulphur is one of the most efficient agents known for killing them, but it will not, however, mix properly with water in its ordinary form, but should be teated according to the following recipe:

Boil together in four gallons of water 1 lb. of flowers of sulphur and 2 lb. of fresh lime, and add 1½ lb. of soft soap, and, before using, 3 gallons more of water, or mix 4 oz of sulphate of lime with half that weight of soft soap, and, when well mixed, add 1 gallon of hot water. Use when cool enough to bear your hand in it. Any insecticide containing sulphur is useful. The walls should be well washed with some insecticide of this kind. Old walls in which the pointing is bad and the bricks full of nail holes, etc., are very difficult to keep free from red spider. They should be painted over with a strong solution of soot water mixed with clay to form a paint. To a gallon of this paint add 1 lb. of flowers of sulphur and 2 oz of soft soap.

This mixture should be thoroughly rubbed with a brush into every crack and crevice of the walls, and if applied regularly every year would probably prevent the trees from being badly attacked. As the red spider passes the winter under some shelter, frequently choosing stones, rubbish, etc., near the roots of the trees, keeping the ground near the trees clean and well cultivated will tend greatly to diminish their numbers. In vineries one of the best ways of destroying these creatures is to paint the hot water pipes with one part of fresh lime and two parts of flowers of sulphur mixed into a paint. If a flue is painted in this way, great care should be taken that the sulphur does not burn, or much damage may be done, as the flues may become much hotter than hot water pipes. During the earlier stages of growth keep the atmosphere moist and impregnated with ammonia by a layer of fresh stable litter, or by painting the hot water pipes with guano made into a paint, as long as the air in the house is kept moist there is not much danger of a bad attack. As soon as the leaves are off, the canes should be dressed with the recipe already given for painting the walls, and two inches or so of the surface soil removed and replaced with fresh and all the wood and iron work of the house well scrubbed. If carnations are attacked, tying up some flowers of sulphur in a muslin bag and sulphuring the plants liberally, and washing them well in three days' time has been recommended.

Tobacco water and tobacco smoke will also kill these pests, but as neither tobacco nor sulphuring the hot water pipes can always be resorted to with safety in houses, by far the better way is to keep a sharp look out for this pest, and as soon as a plant is found to be attacked to at once clean it with an insecticide which it is known the plant will bear, and by this means prevent other plants from being infested. These little mites breed with astonishing rapidity, so that great care should be exercised in at once stopping an attack. A lady friend of mine had some castor oil plants growing in pots in a window which were badly attacked, and found that some lady-birds soon made short work of the mites and cleared the plants. The red spider lays its eggs among the threads of the web which it weaves over the under sides of the leaves; the eggs are round and white; the young spiders are hatched in about a week, and they very much resemble their parents in general appearance, but they have only three pairs of legs instead of four at first, and they do not acquire the fourth pair until they have changed their skins several times; they are, of course, much smaller in size, but are, however, in proportion just as destructive as the older ones. They obtain the juices of the leaves by eating through the skin with their mandibles, and then thrusting in their probosces or suckers (Fig. 2), through which they draw out the juices. These little creatures are so transparent, that it is very difficult to make out all the details of their mouths accurately. The females are very fertile, and breed with great rapidity under favorable circumstances all the year round.

The red spiders, as I have already stated, are not real spiders, but belong to the family Acarina or mites, a family included in the same class (the arachnida) as the true spiders, from which they may be easily distinguished by the want of any apparent division between the head and thorax and body; in the true spiders the head and thorax are united together and form one piece, to which the body is joined by a slender waist. The arachnidæ are followed by the myriapoda (centipedes, etc.), and these by the insectiæ or true insects. The red spiders belong to the kind of mites called spinning mites, to distinguish them from those which do not form a web of any kind. It is not quite certain at present whether there is only one or more species of red spider; but this is immaterial to the horticulturist, as their habits and the means for their destruction are the same. The red spider (Tetranychus telarius--Fig. 1) is very minute, not measuring more than the sixtieth of an inch in length when full grown; their color is very variable, some individuals being nearly white, others greenish, or various shades of orange, and red. This variation in color probably depends somewhat on their age or food--the red ones are generally supposed to be the most mature. The head is furnished with a pair of pointed mandibles, between which is a pointed beak or sucker (Fig. 2). The legs are eight in number; the two front pairs project forward and the other two backward; they are covered with long stiff hairs; the extremities of the feet are provided with long bent hairs, which are each terminated by a knob. The legs and feet appear to be only used in drawing out the threads and weaving the web. The thread is secreted by a nipple or spinneret (Fig. 4) situated near the apex of the body on the under side. The upper surface of the body is sparingly covered with long stiff hairs.--_G.S.S., in The Garden._

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THE HELODERMA HORRIDUM.

The discussion of the curious lizard found in our Western Territories and in Mexico, and variously known as the "Montana alligator," "the Gila monster," and "the Mexican heloderma," is becoming decidedly interesting.

As noted in a recent issue of the SCIENTIFIC AMERICAN, a live specimen was sent last summer to Sir John Lubbock, and by him presented to the London Zoological Gardens. At first it was handled as any other lizard would be, without special fear of its bite, although its mouth is well armed with teeth. Subsequent investigation has convinced its keepers that the creature is not a fit subject for careless handling; that its native reputation is justified by fact; and that it is an exception to all known lizards, in that its teeth are poison fangs comparable with those of venomous serpents.

Speaking of the Mexican reputation of the lizard, in a recent issue of _Knowledge_, Dr. Andrew Wilson, whose opinion will be respected by all naturalists, says that "without direct evidence of such a statement no man of science, basing his knowledge of lizard nature on the exact knowledge to hand, would have hesitated in rejecting the story as, at least, improbable. Yet it is clear that the stories of the New World may have had an actual basis of fact; for the _Heloderma horridum_ has been, beyond doubt, proved to be poisonous in as high a degree as a cobra or a rattlesnake.

"At first the lizard was freely handled by those in charge at Regent's Park, and being a lizard, was regarded as harmless. It was certainly dull and inactive, a result probably due to its long voyage and to the want of food. Thanks, however, to the examination of Dr. Gunther, of the British Museum, and to actual experiment, we now know that _Heloderma_ will require in future to be classed among the deadly enemies of other animals. Examining its mouth, Dr. Gunther found that its teeth formed a literal series of poison fangs. Each tooth, apparently, possesses a poison gland; and lizards, it may be added, are plentifully supplied with these organs as a rule. Experimenting upon the virulence of the poison, _Heloderma_ was made to bite a frog and a guinea pig. The frog died in one minute, and the guinea-pig in three. The virus required to produce these effects must be of singularly acute and powerful nature. It is to be hoped that no case of human misadventure at the teeth of _Heloderma_ may happen. There can be no question, judging from the analogy of serpent-bite, that the poison of the lizard would affect man."

In an article in the London _Field_, Mr. W.B. Tegetmeier states that this remarkable lizard was first described in the _Isis_, in 1829, by the German naturalist Wiegmann, who gave it the name it bears, and noted the ophidian character of its teeth.

In the _Comptes Rendus_ of 1875, M.F. Sumichrast gave a much more detailed account of the habits and mode of life of this animal, and forwarded specimens in alcohol to Paris, where they were dissected and carefully described. The results of these investigations have been published in the third part of the "Mission Scientifique an Mexique," which, being devoted to reptiles, has been edited by Messrs. Aug. Dumeril and Becourt.

The heloderm, according to M.F. Sumichrast, inhabits the hot zone of Mexico--that intervening between the high mountains and the Pacific in the districts bordering the Gulf of Tehuantepec. It is found only where the climate is dry and hot; and on the moister eastern slopes of the mountain chain that receive the damp winds from the Gulf of Mexico it is entirely unknown. Of its habits but little is known, as it appears to be, like many lizards, nocturnal, or seminocturnal, in its movements, and, moreover, it is viewed with extreme dread by the natives, who regard it as equally poisonous with the most venomous serpents. It is obviously, however, a terrestrial animal, as it has not a swimming tail flattened from side to side, nor the climbing feet that so characteristically mark arboreal lizards. Sumichrast further states that the animal has a strong nauseous smell, and that when irritated it secretes a large quantity of gluey saliva. In order to test its supposed poisonous property, he caused a young one to bite a pullet under the wing. In a few minutes the adjacent parts became violet in color, convulsions ensued, from which the bird partially recovered, but it died at the expiration of twelve hours. A large cat was also caused to be bitten in the foot by the same heloderm; it was not killed, but the limb became swollen, and the cat continued mewing for several hours, as if in extreme pain. The dead specimens sent to Europe have been carefully examined as to the character of the teeth. Sections of these have been made, which demonstrate the existence of a canal in each, totally distinct from and anterior to the pulp cavity; but the soft parts had not been examined with sufficient care to determine the existence or non-existence of any poison gland in immediate connection with these perforated teeth until Dr. Gunther's observations were made, as described by Dr. Wilson.

Hitherto, as noted in a previous article, American naturalists have regarded the heloderm as quite harmless--an opinion well sustained by the judgment of many persons in Arizona and other parts of the West by whom the reptile has been kept as an interesting though ugly pet. While the Indians and native Mexicans believe the creature to be venomous, we have never heard an instance in which the bite of it has proved fatal.

A correspondent of the SCIENTIFIC AMERICAN, "C.E.J.," writing from Salt Lake City, Utah, under date of September 8, says, after referring to the article on the heloderm in our issue of August 26:

"Having resided in the southern part of this Territory for seventeen years, where the mercury often reaches 110° or more in the shade, and handled a number of these 'monsters,' I can say that I never yet knew anybody or anything to have perished from their bite. We have often had two or three of them tied in the door-yard by a hind leg, and the children have freely played around them--picking them up by the nape of the neck and watching them snap off a small bit from the end of a stick when poked at them. We have fed them raw egg and milk; the latter they take with great relish. At one time a small canine came too near the mouth of our alligator (_mountain alligator_, we call them), when it instantly caught the pup by the under jaw and held on as only it could (they have a powerful jaw), nor would it release its hold until choked near to death, which was done by taking it behind the bony framework of the head, between the thumb and finger, and pressing hard. The pup did considerable howling for half an hour, by which time the jaw was much swollen, remaining so for two or three days, after which it was all right again. By this I could only conclude that the animal was but slightly poisonous. I never knew of a human being having been bitten by one. My sister kept one about the house for several weeks, and fed it from her hands and with a spoon. The specimens have generally been sent (through the Deseret Museum) to colleges and museums in the East.

"The Indians have a great fear that these animals produce at will good or bad weather, and will not molest them. Many times they have come to see them, and told us that we should let them go or they would talk to the storm spirit and send wind and water and fire upon us. An old Indian I once talked with told me of another who was bitten on the hand, and said it swelled up the arm badly, but he recovered. From some reason we never find specimens less than 12 or 14 inches long, I never saw a young one. There is a nice stuffed specimen, 18 inches long, in our museum here."

Sir John Lubbock's specimen, shown in the engraving herewith, for which we are indebted to the London _Field_, is about 19 inches in length. Its general color is a creamy buff, with dark brown markings. The forepart of the head and muzzle is entirely dark, the upper eyelid being indicated by a light stripe. The entire body is covered with circular warts. It is fed upon eggs, which it eats greedily.

It would be interesting to know whether the northern specimens, if venomous at all, are as fully equipped with poison bags and fangs as Dr. Gunther finds the Mexican specimen to be. Some of our Western or Mexican readers may be able to make comparative tests. Meantime it would be prudent to limit the use of the "monster" as a children's pet.

The foregoing appeared in the SCIENTIFIC AMERICAN of Oct. 7, 1882.

We are now indebted to a correspondent, Mr. Wm. Y. Beach, of the Grand View Mine, Grant County, Southern Arizona, for a fine specimen of this singular reptile, just received alive. The example sent to us is about twenty inches long, and answers very well to the description of the monster and the engraving above given.

In the course of an hour after opening the box in which the reptile had been confined during its eight days' journey by rail, it became very much at home, stretching and crawling about our office floor with much apparent satisfaction.

Our correspondent is located in the mountains, some nine miles distant from the Gila River. He states that the reptile he sends was found in one of the shops pertaining to the mine, which had been left unoccupied for a week or so.

Apropos to the foregoing, we have received the following letter from another correspondent in Arizona:

_To the Editor of the Scientific American:_

My attention has been called to an article in your issue of Oct. 7, 1882, relating to the _Heloderma horridum_, or commonly known as the Gila Monster.

During a residence of ten years in Arizona I have had many opportunities of learning the habits of these reptiles, and I am satisfied their bite will produce serious effects, if not death, of the human race. I know of one instance where a gentleman of my acquaintance by the name of Bostick, at the Tiga Top mining camp, in Arizona, was bitten on the fingers, and suffered all the symptoms of poison from snake bite. He was confined to his bed for six weeks and subsequently died. I am of the opinion his death was in part caused by the effects of the poison of the Gila Monster.

The Hualzar Indians are very much afraid of them, and one I showed the picture to of the Monster in your paper remarked, "Chinamuck," which in Hualzar language means "very bad." He said if an Indian is bitten, he sometimes dies.

I have seen them nearly two feet in length. Never, to my knowledge, are they kept as pets in our portion of Arizona. They live on mice and other small animals, and when aggravated can jump several times their length.

W.E. DAY, M.D.

Huckberry, Mahone Co., Ar. T., April, 1883.

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THE KANGAROO.

_To the Editor of the Scientific American:_

In page 69 of your issue of 3d of February, 1883, I notice among the "Challenger Notes" of Professor Mosely the statement that "Among stockmen, and even some well educated people in Australia, there is a conviction that the young kangaroo grows out as a sort of bud on the teat of the mother within the pouch." Some eighteen months ago I noticed a paragraph wherein some learned professor was reported to have set at rest the contested point as to whether the kangaroo come into being in the same manner as the calves of the cow and other mammals, or whether the young grows, as alleged, upon the teat of its dam within the pouch. The learned professor in question asserted that it did not so grow upon the teat; but, with all due respect to the professor's claim to credibility on other matters, I must in this instance take the liberty of stating that he is in error. The young kangaroo actually oozes out, if I may use such an expression, from the teat. Strange as the statement may seem, it is a fact that the first indication of life on the part of the kangaroo offspring is a very slight eruption, in size not larger than an ordinary pin head. This growth gradually resolves itself into the form of the marsupial, and is not detached until close upon the expiring of of the fourth month. It is carried by the mother during that period, and thenceforth exists partially at least on herbage. Indeed, from the fourth till the seventh month it is almost constantly in the pouch, only coming out occasionally toward the close of evening to crop the grass. I had at one time in my possession a specimen of the kangaroo germ which I cut from off the teat, complete in form, whose entire weight was less than an ounce; and, at the same time, I had a kangaroo in my possession which measured seven feet six inches from the top of the ears to the extremity of the tail.

Your readers would doubtless feel interested with a few particulars as to my life among the kangaroos in a genuine kangaroo country. I have read somewhere about the exceeding beauty of the eyes of the gazelle; how noted hunters have alleged that their nature so softened on looking into the animal's eyes that they (the hunters) had no heart to destroy the creature. Now, I have never seen a gazelle, and so cannot indulge in comparisons; but if their eyes are more beautiful than those of a middle-aged kangaroo, they may indeed be all that huntsmen say of them. With respect to the old kangaroos, their eyes and face are simply atrocious in their repulsive ugliness.

Nothing in nature could surpass the affection which the female kangaroo manifests for her young. There is something absolutely touching in the anxious solicitude displayed by the dam while the young ones are at play. On the least alarm the youngster instantly ensconces himself in the pouch of his gentle mother, and should he, in the exuberance of his joy, thrust his head out from his place of refuge, it is instantly thrust back by his dam. I have, on several occasions, by hard riding, pressed a doe to dire extremity, and it has only been when hope had entirely forsaken her, or when her capture was inevitable, that she has reluctantly thrown out the fawn. Their method of warfare has often reminded me of the style of two practiced pugilists, the aim of each being to firmly gripe his opponent by the shoulder, upon accomplishing which, the long hind leg, with its horny blade projecting from its toe, comes into formidable play. It is lifted and drawn downward with a rapid movement, and one or other of the combatants soon shows the entrails laid bare, which is usually the _grand finale_. The sparring that takes place between the marsupials while trying to get the advantageous gripe is marvelous--I had almost said scientific; for the style and rapidity of the animals' movements might excite the admiration of the Tipton Slasher.