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means look upon these
of the following very inter
one of the precepts of Providence that seems strange Few, if any, organs belonging to the diferent
We have taken a cursory glance at the main features of the Cuttles, animals which, from their fero
THE ANTENNÆ OF INSECTS. cious disposition and terrible weapons, may fairly
BY MR. T. W. WONFOR. rank as the tigers of the deep. Yet we must by no
esting and On the contrary, they are most necessary, and are a before the Brighton Natural History Society, from part of the scheme of nature by means of which the Brighton Daily News, a paper which has already creatures are kept within bounds from excessive distinguished itself by the prominence it gives to increase through counterbalancing causes. It is į popular scientific subjects. and revolting at first sight, that throughout all members of the animal world present such a divercreation there should be such a sanguinary scene as sity of form, or have led to so great a difference of that of the cruel methods by which the carnivorous opinion among naturalists respecting the special tribes procure their prey. As it is with the higher office they fulfil in the animal economy as the an. mammalia, so is it with these cuttles; the more the tenne, the jointed organs situated on the head in difficulties and dangers that beset the existence of most of the different members of the great family of an animal, the more are its means of defence aug.
articulata. While the crustacea possess two pair, mented. The pursuit of prey forms a large part of the myriapoda and insecta are furnished with a single the occupation of the Cuttles, as also does flight pair only; in the last-named the form, number of from their numerous foes. These twofold require- joints, and sundry other particulars are used as a ments bring into action a number of accomplish means of classifying the different genera and species. ments, so to speak, which, but for their carnivorous They are generally spoken of as consisting of three nature and that of their enemies, would never have parts,--the basal joint, connected with the head by been called into existence. But for the urgent calls a ball-and-socket movement called the torulus, is for self-preservation, ļboth as shown in flight froin designated by the term scapus ; the next portion, enemies and pursuit of prey, a great sameness and generally cylindrical in form and often very minute inactivity would be visible in all the manifold pro in size, is called the pedicella ; while the rest of the ductions of nature. It was never meant that antenna is called the clavola. That the form is animals should drag on a miserable existence merely different is evident to all who have examined any to keep gorging themselves with food. No; under class of insects, while the terms moniliform, setasuch a state of affairs what would be the aspect the ceous, clavate, pectinated, ensiform, plumose, lamelworld would present ? A number of beings grovel. late, &c., indicate the nature of some of these differling on the earth with no other care than that of ences; and simply as objects exhibiting diversity filling their paunches to satiety, and totally destitute of appearance with possible identity of office, they of the life and busy activity which is to be seen form an instructive series worthy the attention of everywhere around under the present state of affairs. the microscopist. The sudden extinction of all cuttles would also Apart from this diversity of form, the antennæ create a great blank in the police of nature; we deserve especial attention, because, as before menshould have several creatures increasing at such a tioned, it is not yet absolutely determined what is rate as to become positivelg baneful. It is interest their especial function, or in which part any one of ing to notice the many forms which cuttles possess, the functions attributed to them is situated. all called into being by a felt need. The female Different writers have assigned to the antennæ the Argonauta fabricates a delicate shell wherein her three several senses of touch, hearing, and smelling, eggs are laid to prevent their being injured by the and all adduce illustrations, or the existence of parts rapid rush of water or devoured by predacious in these organs, to warrant their respective views. fishes; the male, having no eggs to protect, does not That they are organs of sensation none deny, but require a shell, and so has not got one. Nearly all which, or how many of the three senses above named cuttle are provided with a supply of ink to aid them they constitute, is still a moot question, though the in escaping from their enemies, by rendering the microscope in the hand of Dr. Hicks and others has water so dark and turbid that they are not visible. done much in recent days to help to unravel the Yet the Nautilus bas no ink—and why? Because mystery. its mode of protecting itself is by simply retreating Those who have watched the actions of ants or within the shell, where it is perfectly protected bees must have been struck with the use made by from all foes by the strong membrane which forms these creatures of their antenne, as a means of a cover to the mouth of the shell. And we might communicating information to each other. How multiply instances indefinitely, but the few above this information is conveyed, or how they converse, will show how a variety of powers is called forth by apparently, by the mere contact of their antenne is the needs of self-preservation.
certainly not known; but that they do convey infor
mation from one to another, ask for help, and give while the former have alighted from a considerable orders, is borne out by the observations of many height on their favourite flowers. Then, as is well diligent students of both the tribes.
known to lepidopterists, night-flying moths are That in many cases they are admirably adapted as attracted from long distances by anointing the organs of touch or feeling would appear to be the trunks of trees with sugar or treacle, and this, we case from the great number of joints, their extreme should think, by the sense of smell alone. delicacy, and the easiness of movement in every Again, as we have stated on several occasions, direction. Many insects, when at rest, fold back the males of some species of moths are attracted by the antennæ, so as to conceal them, but as soon as the females under such conditions as to lead to the they begin to move, the antennæ are thrust forward, idea that either the sense of smell is wonderfully the parts are separated widely, and while in some acute, or that they possess some sense not yet deterthey are vibrated from side to side, in others, as in mined by physiologists. Placed in boxes either some species of wood lice (as observed by Kirby and carried in the coat-pocket, put in a basket, or shut Spence), they are used as organs of touch. It has up in a leather bag, the perceptive faculty has been been urged that they cannot well be organs of touch, so strong in the male that they have been seen on account of the hard horny character of their flying over the top of a wood at least 300 yards off. outer surfaces, and that this function is performed Nay more, we have bad them settle upon ourselves by another set of organs,—the palpi.
when the box containing the female was no longer Many naturalists incline to the idea that they are in the pocket. Our idea is that some of the (to us) the organs of hearing. Now it is generally conceded | imperceptible scent clung to our garment. that in the crustacea, especially the higher ones, the Among the authorities inclining to the idea that organs of hearing are situated at the base of the long the antennæ are the organs of hearing are Sulzer, external pair of antennæ, and, as in the case of the Scarpa, Schneider, Rockhauser, Burmeister, Carus, crayfish, consist of a hollow cylindrical process, Oxen, Kirby and Spence, Newport, and Hicks : the closed internally by a drum or thin membrane, behind last named we have more particularly to refer to which is a vesicle filled with fluid, which receives presently. On the side of those who consider them the termination of a nerve; but the organ of smell, organs of smell are Reaumer, Lyonet, Robinea, as bas been principally observed with crabs, consists Desvoidy, Küster, Erichson, and Vogt. of cavities lined with a mucous membrane, situated It might be asked-Has the microscope done at the base of the inner pair of antenne, and pro anything, and if so, what, in solving these difficultected externally by fine bristles.
ties? Newport in 1831 (“Transactions of the Many observers have noticed that, if a noise is Entomological Society," vol. ii. p. 229) found all made, the 'antennæ of some insects are turned in the joints, except the second, of Ichneumon Atropos the direction of the part from which the noise comes. perforated all round by very minute holes. He This has been observed in the case of the longicorn observed also tracheæ passing up the whole length beetles, grasshoppers, and crickets, which, when of the antennæ, and giving off branches at every suddenly surprised by a noise, have been seen to joint, and which, as he considered, communicated stretch out their long antennæ and stand, as it were, with the holes in the wall of the antennæ. Of this, attentively listening for the sound. Rennie mentions though, he was not quite certain. He states ithat a green grasshopper inclining its antennæ to the the same structureexisted in most setaceous antennæ. rustle of a piece of paper under the table on which E. F. Erichson published at Berlin, in 1847, his it was placed, and bending one of them in the direc “Dissertaito de Fabricâ et Usu Antennarum in tion of the sound.
Insectis," in which he enunciated these laws: 1st. The On the other hand, many circumstances seem to wall of the antenne in insects is by no means solid, prove that insects possess a (very acute sense of but perforated by numerous openings. 2nd. These smell. It has been observed in "Episodes of openings are closed on the inner side by a memInsect Life” that "no flocks of vultures can be brane. 3rd. The openings in the antennæ of differdirected more unerringly to their revolting prey by ent insects are arranged in different ways. He also its odours from afar than certain insects, such as shows that these openings are never found in the dung-flies and carrion beetles, whose corresponding basal joint. He considered the numerous hairs office is to assist in ridding the earth of offensive found in the antennæ, between the pores or openobjects." That it is the sense of smell which ings, protected them from extraneous bodies, and directs the blow-fly to the deposition of the larve that the pores were organs of smell, because, is shown by the fact that she has laid them on sta the olfactory organs of the higher animals are moist pelias, a carrion-odoured hothouse plant, and on membranes, in order that the odorous particles may silk with which tainted meat had been covered. be dissolved by the humour secreted, in the same Equally keen-scented are butterflies and bees; the way these membranes 'perform the same office, are latter have flown miles in the direction of particular protected by the downy hairs, and kept moist by flowers, whose odour had been wafted by the wind,' them.” Another reason why he considered them
organs of smell was that they are most numerous in not only the shape of the antenne in the sexes those tribes of insects whose scent is acute. Vogt differs in a marked degree, but the pectination in pointed out in 1851 that “if the uniform antenne the males is very deep, and the number of hairs is are examined with a sufficiently high power, the many times greater than in the female, while the outer surface of all the divisions, except the articu organs pointed out by Dr. Hicks are more numerous. lating joint, is found to be covered with minute This is a good time of year for such members as may punctures, which are closed in at the bottom by a feel; an interest in the subject to investigate the thin membrane that appears to be clothed with matter for themselves, and we would advise that pumerous hairs. In the antennæ that are not of not only the method of bleaching recommended for uniform shape throughout, there is a shaft or style, rendering the antennæ more transparent be adopted, and these indentations are then found only upon the but that sections similar to those so admirably made toothed branches, processes, and feathers of the by Dr. Halifax be tried, and so some further light antennæ, whilst the integument of the shaft is like may be thrown, either way, on these organs, though that of the remaining portions of the body." He the question whether they be confined to one sense, further says of them, “We are of opinion that these or whether they perform the office at times assigned minute pores, filled with fine hairs, perform a func to them of common sensation, may not be made out tion combining those of smell and touch. Now to demonstration. The process recommended for Dr. Hicks, in two papers read before the bleaching by Dr. Hicks is one drachm chlorate of Linnæan Society in 1857 and 1859, and published potash, one drachm and a half water; mix in a in the 22nd vol, of 'The Transactions of the Linnean small wide-mouth bottle holding about an ounce; Society,' pointed out that on the whole surface of after five minutes add 1} drachm of strong hydrothe third joint of the antenne of the blow-fly are a chloric acid. In this mixture place antennæ, and let multitude of transparent dots, apparently vesicles, them remain from a few hours to a week, according which on closer examination are found to be cavities to their nature. in the wall of the antennæ, filled with fluid, closed in from the outer air by a very thin membrane, and that each little sac is connected with the nervous
THE GOLD-CRESTED WREN. system by a distinct nerve.” There are 17,000 of these perforations on the surface of each antenna
By W. H. WARNER. in the blow-fly. Besides these, there are about
of the tall, graceful, and swaying spruce-firs persed, and connected with the nervous ganglia. (Abies excelsa), and here, at various times of the He points out the existence of similar organs in the year, but especially in spring and summer, may be antennæ of the different tribes of insects, and comes seen a pair or more of those extremely beautifal to the conclusion that they are organs of hearing, little birds the Golden-crested Wrens (Regulus crisbecause—"1st, they consist of a cell, sac, or cavity | tatus), the humming-bird of the British isles. This filled with fluid, closed in from the air by a mem tiny bird is about three inches and a half in length, . brane analogous to that which closes the foramen with plumage of an olive-green, and a pale yellow ovale in the higher animals; 2nd, that this membrane crown, bordered with black at the top of the head. is for the most part thin and delicate, but often In the male bird a dash of orange enriches his golden projects above the surface, in either a hemispherical, crown, giving him a still further claim to the title of conical, or canoe-shaped, or even hair-like form, Regulus--a king. often variously marked ; 3rd, that the antennal You may see the tiny Gold-crest in the most nerve gives off branches which come in contact with lonely woods, as well as near houses, but always the inner wall of the sacs; but whether the nerve among trees of the fir tribe, for which it has an enters or ends in the small internally projecting especial predilection. And here it hunts for minute papilla is very difficult to say. Dr. Hicks considered insects the livelong day with the greatest industry, it impossible that the essential nature of an olfactory disporting itself in all manner of positions. It flutters organ could be included in such structures, or that like a butterfly from bough to bough, peers with its odorous particles could pass, first through a meni. bright eye into every cranny and crevice, hangs brane, sometimes even spinous, then through a head downwards like the restless tits, and is genecavity filled with fluid, and thirdly through another rally so absorbed in its busy search, that it will membrane to reach the extremity of a nerve, but allow the spectator to approach quite close withthat they were well suited to the transmission of out its testifying the slightest alarm. So fearless sound. Notwithstanding the conclusions of Dr. too is its disposition, thut I have several times Hicks, we cannot help thinking that one of the approached within arm's length of it. During the functions of the antennæ is that of smell. In those severe weather which ushered in the year 1871, moths which exbibit "sembling," that is, the attract a little Gold-crest came to receive our bounty, and ing the males by the female from long distances, on one occasion fluttered down to my feet with the
eighty larger sacculated chambers irregularly dist SHELTERING one side of the house is a row
greatest confidence and trust. hen busily hunt in the aviary. Bechstein, that great authority on ing for food among the boughs of the pine and the such matters, says that the young Gold-crests may fir, the Gold-crest frequently repeats its sbrill call. be easily reared if taken before they are fully fledged. note, which closely resembles the sharp squeak of He recommends as food, meal-worms cut small, the Shrew. Its song proper is a sweet feeble little flies, ants’-eggs, and wheaten bread soaked in milk: strain, consisting of a few short notes—tweetie, care must be taken to make the latter neither too tweetie ! ending in a long-drawn twee! This is stiff nor too moist. He also says that insect food repeated while the tiny performer is swaying about is necessary to them and seeds injurious. These on the branches of the fir. It first begins to sing pretty little creatures live and thrive well in a in February (in mild seasons in January) and on warmed and ventilated greenhouse with a small pinetill August or September.
tree in the centre, or a large cage in a moderately At the end of April or the beginning of May, the Gold-crest begins to exercise its skill as a designer Kingston, Abingdon. and weaver, and in this accomplishment it bas but three rivals among the British birds ; viz., the Chaffinch, the Goldfinch, and the Long-tailed Tit.
PARASITIC FLIES. Early in May, 1868, I watched the progress of a
nest, which was built in a spruce-fir close to this BY this term I do not mean the
hosts of black
-, id materials in their bills, I watched them for some omne, which try men's patience and temper by time, and at length discovered the nest at the sucking their blood; but a still worse "crew," extreme end of one of the fir boughs. The tiny whose mission it is to deposit eggs either upon or owners worked most industriously, and in the space within the human body. In these cases it is the of a week the nest was completed, and two eggs larva or grub which works all the mischief. The laid. The nest hung between two small end boughs, period of occupancy occurs before the perfect insect to one of which it was attached by ropes of cocoon comes to light; and therefore man's tenant, in the silk, and the other was woven in with the materials instances to wbich I allude, is the grub,-not of the nest. The nest was about four inches and the fly. a half in length, and was moulded and woven in the most neat and beautiful manner. It was open above, and the opening abruptly narrowed as it reached the top. The walls were composed of soft green moss and wool, felted together and covered on the outside with the webs of spiders, the cocoons of insects, and a few shreds of bark. The inside was small and plentifully lined with feathers, which near the top were so arranged as to almost hide Fig. 27. “Whorbles," or “ Worm-holes," in hides of oxen. the opening. In this soft bed the eggs were laid, and from their diminutive size appeared almost The last place perhaps in which one would look lost among the feathers with which the hollow was for the larva of a flower-fly (I know no better so plentifully adorned. The eggs were of a delicate way of rendering the technical name, Anthomyia) cream-colour, with a pale brown zone or band at is the buman stomach. Yet at least two species the large end.
(scalaris and canicularis) occasionally occupy this In June the Gold-crest brings out its little family singular locality. How can they get there ? is the into public life, and they hunt for food in company, first and most natural question; but one which it resorting frequently in winter to the hawthorn is by no means easy to solve. The most probable hedges, and often collecting into flocks of some suggestion is that they are introduced with vegenumbers. Selby affirms that this tiny creature tables which have been standing for some time, and sometimes migrates, and says that in October, 1822, on which the mother-fly has," in the innocence of after a very heavy gale and fog from the N.W., her heart, laid a batch of eggs, unwitting of the thousands of these birds were seen to arrive on the evil consequences likely to follow. But in whatseashore and sandbanks of the Northumbrian ever way they have been brought into their temcoasts.
porary lodgings, they appear to adapt themselves To conclude. Though not an advocate for keep- readily to surrounding circumstances, and to make ing birds in confinement, having always preferred themselves quite at home, clinging to the inner surstudying the really wild denizens of the woods and face of the intestine by means of minute spines fields, yet in deference to those wbo hold a contrary with which the back and sides are armed. While opinion, I may as well give a few second-hand there, they cause, as may be supposed, considerable hints as to the management of these tiny creatures irritation.
this way it has often caused serious annoyance and even danger to life, laying its eggs in hot weather on wounds and sores, where they speedily hatch, and the grubs, instead of dropping to the ground, eat their way into the flesh. A terrible story is given by Kirby and Spence (Introduction vol. i. p. 137, ed. 4), of a beggar being almost literally devoured alive by the larvæ of flies, attracted by some meat placed by the wretched man "betwixt his shirt and skin.”
The principal parasites, at least in this country, are the different kinds of Flesh-fly (Sarcophaga, fig. 29) and Blow-fly or Blue-bottle (Calliphora, fig. 30), the prolific parent of the “gentles," dear to the heart of youthful Izaak Waltons. Prolific indeed they are ! Degeer calculated that a single flesh-fly may deposit about fifty larvæ (for she is viviparous), and in the course of six months may become the happy mother of more than five hundred million descendants! (Lennis, "Naturgeschichte des Thierreichs," s. 620.)
In addition to the above there are two flies, whose habits have not been thoroughly studied; but the effect of whose parasitism is, in one case at least, very serious. They are confined to the warmer regions of America, and are known to the natives under various names : in Brazil they are the Ura; in Costa Rica, the Torcel; in New Granada, the Gusano peludo; in Cayenne, the Ver macaque. With regard to one of these flies, Bates speaks as follows:-"A species of Estrus or gadily, on the Upper Amazons, fixes on the flesh of man as a breeding-place for its grub. I extracted five at different times from my own flesh. The first was fixed in the calf of my leg, causing there a suppurating tumour, which (being unaware of the existence of this Estrus) I thought at first was a common boil. The tumour grew, and the pain increased until I became quite lame, and then, on carefully examining the supposed boil, I saw the head of a grub moving in a small hole at its apex. The extraction of the animal was a difficult opera. tion, it being an inch in length and of increasing breadth from head to tail, besides being secured to the flesh of the inside of the tumour by two horny
Fig. 30. Blow-fly (Calliphora fulvibarbis).
A similar story of a not less painful nature is recorded by M. Aristide Roger, in his “Les Monstres invisibles” (p. 55). It has reference to the death of a chiffonier, who was found a few years ago in a ditch just outside Paris, still living, but with his features completely destroyed by the multitude of blow-fly grubs feeding on him.
Man's perverse ingenuity has converted this propensity of flies to devour living flesh into an instrument of torture; for Plutarch assures us, that in Persia state criminals were sometimes thus punished. For this purpose the wretched individual