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We have taken a cursory glance at the main features of the Cuttles, animals which, from their ferocious disposition and terrible weapons, may fairly rank as the tigers of the deep. Yet we must by no

THE ANTENNE OF INSECTS.

BY MR. T. W. WONFOR.

means look upon these destroyers as beings whose WE copy the report of the following very inter

absence would leave no gap, or be even beneficial. On the contrary, they are most necessary, and are a part of the scheme of nature by means of which creatures are kept within bounds from excessive increase through counterbalancing causes. It is one of the precepts of Providence that seems strange and revolting at first sight, that throughout all creation there should be such a sanguinary scene as that of the cruel methods by which the carnivorous tribes procure their prey. As it is with the higher mammalia, so is it with these cuttles; the more the difficulties and dangers that beset the existence of an animal, the more are its means of defence aug. mented. The pursuit of prey forms a large part of the occupation of the Cuttles, as also does flight from their numerous foes. These twofold requirements bring into action a number of accomplishments, so to speak, which, but for their carnivorous nature and that of their enemies, would never have been called into existence. But for the urgent calls for self-preservation, both as shown in flight from enemies and pursuit of prey, a great sameness and inactivity would be visible in all the manifold productions of nature. It was never meant that animals should drag on a miserable existence merely to keep gorging themselves with food. No; under such a state of affairs what would be the aspect the world would present? A number of beings grovelling on the earth with no other care than that of filling their paunches to satiety, and totally destitute of the life and busy activity which is to be seen everywhere around under the present state of affairs. The sudden extinction of all cuttles would also create a great blank in the police of nature; we should have several creatures increasing at such a rate as to become positively baneful. It is interesting to notice the many forms which cuttles possess, all called into being by a felt need. The female Argonauta fabricates a delicate shell wherein her eggs are laid to prevent their being injured by the rapid rush of water or devoured by predacious fishes; the male, having no eggs to protect, does not require a shell, and so has not got one. Nearly all cuttle are provided with a supply of ink to aid them in escaping from their enemies, by rendering the water so dark and turbid that they are not visible. Yet the Nautilus has no ink-and why? Because its mode of protecting itself is by simply retreating within the shell, where it is perfectly protected from all foes by the strong membrane which forms a cover to the mouth of the shell. And we might multiply instances indefinitely, but the few above will show how a variety of powers is called forth by the needs of self-preservation.

esting and instructive paper, recently read before the Brighton Natural History Society, from the Brighton Daily News, a paper which has already distinguished itself by the prominence it gives to popular scientific subjects.

Few, if any, organs belonging to the different members of the animal world present such a diversity of form, or have led to so great a difference of opinion among naturalists respecting the special office they fulfil in the animal economy as the antennæ, the jointed organs situated on the head in most of the different members of the great family of articulata. While the crustacea possess two pair, the myriapoda and insecta are furnished with a single pair only; in the last-named the form, number of joints, and sundry other particulars are used as a means of classifying the different genera and species.

They are generally spoken of as consisting of three parts, the basal joint, connected with the head by a ball-and-socket movement called the torulus, is designated by the term scapus; the next portion, generally cylindrical in form and often very minute in size, is called the pedicella; while the rest of the antenna is called the clavola. That the form is different is evident to all who have examined any class of insects, while the terms moniliform, setaceous, clavate, pectinated, ensiform, plumose, lamellate, &c., indicate the nature of some of these differences; and simply as objects exhibiting diversity of appearance with possible identity of office, they form an instructive series worthy the attention of the microscopist.

Apart from this diversity of form, the antennæ deserve especial attention, because, as before mentioned, it is not yet absolutely determined what is their especial function, or in which part any one of the functions attributed to them is situated.

Different writers have assigned to the antennæ the three several senses of touch, hearing, and smelling, and all adduce illustrations, or the existence of parts in these organs, to warrant their respective views. That they are organs of sensation none deny, but which, or how many of the three senses above named they constitute, is still a moot question, though the microscope in the hand of Dr. Hicks and others has done much in recent days to help to unravel the mystery.

Those who have watched the actions of ants or bees must have been struck with the use made by these creatures of their antennæ, as a means of communicating information to each other. How this information is conveyed, or how they converse, apparently, by the mere contact of their antennæ is certainly not known; but that they do convey infor

mation from one to another, ask for help, and give orders, is borne out by the observations of many diligent students of both the tribes.

That in many cases they are admirably adapted as organs of touch or feeling would appear to be the case from the great number of joints, their extreme delicacy, and the easiness of movement in every direction. Many insects, when at rest, fold back the antennæ, so as to conceal them, but as soon as they begin to move, the antennæ are thrust forward, the parts are separated widely, and while in some they are vibrated from side to side, in others, as in some species of wood lice (as observed by Kirby and Spence), they are used as organs of touch. It has been urged that they cannot well be organs of touch, on account of the hard horny character of their outer surfaces, and that this function is performed by another set of organs,-the palpi.

Many naturalists incline to the idea that they are the organs of hearing. Now it is generally conceded that in the crustacea, especially the higher ones, the organs of hearing are situated at the base of the long external pair of antennæ, and, as in the case of the crayfish, consist of a hollow cylindrical process, closed internally by a drum or thin membrane, behind which is a vesicle filled with fluid, which receives the termination of a nerve; but the organ of smell, as has been principally observed with crabs, consists of cavities lined with a mucous membrane, situated at the base of the inner pair of antennæ, and protected externally by fine bristles.

Many observers have noticed that, if a noise is made, the antennæ of some insects are turned in the direction of the part from which the noise comes. This has been observed in the case of the longicorn beetles, grasshoppers, and crickets, which, when suddenly surprised by a noise, have been seen to stretch out their long antennæ and stand, as it were, attentively listening for the sound. Rennie mentions a green grasshopper inclining its antennæ to the rustle of a piece of paper under the table on which it was placed, and bending one of them in the direction of the sound.

On the other hand, many circumstances seem to prove that insects possess a very acute sense of smell. It has been observed in "Episodes of Insect Life" that "no flocks of vultures can be directed more unerringly to their revolting prey by its odours from afar than certain insects, such as dung-flies and carrion beetles, whose corresponding office is to assist in ridding the earth of offensive objects." That it is the sense of smell which directs the blow-fly to the deposition of the larvæ is shown by the fact that she has laid them on stapelias, a carrion-odoured hothouse plant, and on silk with which tainted meat had been covered. Equally keen-scented are butterflies and bees; the latter have flown miles in the direction of particular flowers, whose odour had been wafted by the wind,

while the former have alighted from a considerable height on their favourite flowers. Then, as is well known to lepidopterists, night-flying moths are attracted from long distances by anointing the trunks of trees with sugar or treacle, and this, we should think, by the sense of smell alone.

Again, as we have stated on several occasions, the males of some species of moths are attracted by the females under such conditions as to lead to the idea that either the sense of smell is wonderfully acute, or that they possess some sense not yet determined by physiologists. Placed in boxes either carried in the coat-pocket, put in a basket, or shut up in a leather bag, the perceptive faculty has been so strong in the male that they have been seen flying over the top of a wood at least 300 yards off. Nay more, we have had them settle upon ourselves when the box containing the female was no longer in the pocket. Our idea is that some of the (to us) imperceptible scent clung to our garment.

Among the authorities inclining to the idea that the antennæ are the organs of hearing are Sulzer, Scarpa, Schneider, Rockhauser, Burmeister, Carus, Oxen, Kirby and Spence, Newport, and Hicks: the last named we have more particularly to refer to presently. On the side of those who consider them organs of smell are Reaumer, Lyonet, Robinea, Desvoidy, Küster, Erichson, and Vogt.

It might be asked-Has the microscope done anything, and if so, what, in solving these difficulties? Newport in 1831 (“Transactions of the Entomological Society," vol. ii. p. 229) found all the joints, except the second, of Ichneumon Atropos perforated all round by very minute holes. He observed also trachea passing up the whole length of the antennæ, and giving off branches at every joint, and which, as he considered, communicated with the holes in the wall of the antennæ. Of this, though, he was not quite certain. He states that the same structure existed in most setaceous antennæ. E. F. Erichson published at Berlin, in 1847, his "Dissertaito de Fabricâ et Usu Antennarum in Insectis," in which he enunciated these laws: 1st. The wall of the antennæ in insects is by no means solid, but perforated by numerous openings. 2nd. These openings are closed on the inner side by a membrane. 3rd. The openings in the antennæ of different insects are arranged in different ways. He also shows that these openings are never found in the basal joint. He considered the numerous hairs found in the antennæ, between the pores or openings, protected them from extraneous bodies, and that the pores were organs of smell, because, 89 the olfactory organs of the higher animals are moist membranes, in order that the odorous particles may be dissolved by the humour secreted, in the same way these membranes perform the same office, are protected by the downy hairs, and kept moist by them." Another reason why he considered them

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organs of smell was that they are most numerous in those tribes of insects whose scent is acute. Vogt pointed out in 1851 that "if the uniform antennæ are examined with a sufficiently high power, the outer surface of all the divisions, except the articulating joint, is found to be covered with minute punctures, which are closed in at the bottom by a thin membrane that appears to be clothed with numerous hairs. In the antennæ that are not of uniform shape throughout, there is a shaft or style, and these indentations are then found only upon the toothed branches, processes, and feathers of the antennæ, whilst the integument of the shaft is like that of the remaining portions of the body." He further says of them, "We are of opinion that these minute pores, filled with fine hairs, perform a function combining those of smell and touch. Now

Dr. Hicks, in two papers read before the Linnæan Society in, 1857 and 1859, and published in the 22nd vol. of 'The Transactions of the Linnean Society,' pointed out that on the whole surface of the third joint of the antennæ of the blow-fly are a multitude of transparent dots, apparently vesicles, which on closer examination are found to be cavities 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 system by a distinct nerve." There are 17,000 of these perforations on the surface of each antenna in the blow-fly. Besides these, there are about eighty larger sacculated chambers irregularly dispersed, and connected with the nervous ganglia. He points out the existence of similar organs in the antennæ of the different tribes of insects, and comes to the conclusion that they are organs of hearing, because-"1st, they consist of a cell, sac, or cavity filled with fluid, closed in from the air by a membrane analogous to that which closes the foramen ovale in the higher animals; 2nd, that this membrane is for the most part thin and delicate, but often projects above the surface, in either a hemispherical, conical, or canoe-shaped, or even hair-like form, often variously marked; 3rd, that the antennal nerve gives off branches which come in contact with the inner wall of the sacs; but whether the nerve enters or ends in the small internally projecting papilla is very difficult to say. Dr. Hicks considered it impossible that the essential nature of an olfactory organ could be included in such structures, or that odorous particles could pass, first through a meni. brane, sometimes even spinous, then through a cavity filled with fluid, and thirdly through another membrane to reach the extremity of a nerve, but that they were well suited to the transmission of sound. Notwithstanding the conclusions of Dr. Hicks, we cannot help thinking that one of the functions of the antennæ is that of smell. In those moths which exhibit "sembling," that is, the attracting the males by the female from long distances,

not only the shape of the antennæ in the sexes differs in a marked degree, but the pectination in the males is very deep, and the number of hairs is many times greater than in the female, while the organs pointed out by Dr. Hicks are more numerous. This is a good time of year for such members as may feel an interest in the subject to investigate the matter for themselves, and we would advise that not only the method of bleaching recommended for rendering the antennæ more transparent be adopted, but that sections similar to those so admirably made by Dr. Halifax be tried, and so some further light may be thrown, either way, on these organs, though the question whether they be confined to one sense, or whether they perform the office at times assigned to them of common sensation, may not be made out to demonstration. The process recommended for bleaching by Dr. Hicks is one drachm chlorate of potash, one drachm and a half water; mix in a small wide-mouth bottle holding about an ounce ; after five minutes add 1 drachm of strong hydrochloric acid. In this mixture place antennæ, and let them remain from a few hours to a week, according to their nature.

SHI

THE GOLD-CRESTED WREN.

BY W. H. WARNER.

HELTERING one side of the house is a row of the tall, graceful, and swaying spruce-firs (Abies excelsa), and here, at various times of the year, but especially in spring and summer, may be seen a pair or more of those extremely beautiful little birds the Golden-crested Wrens (Regulus cristatus), the humming-bird of the British isles. This tiny bird is about three inches and a half in length, . with plumage of an olive-green, and a pale yellow crown, bordered with black at the top of the head. In the male bird a dash of orange enriches his golden crown, giving him a still further claim to the title of Regulus-a king.

You may see the tiny Gold-crest in the most lonely woods, as well as near houses, but always among trees of the fir tribe, for which it has an especial predilection. And here it hunts for minute insects the livelong day with the greatest industry, disporting itself in all manner of positions. It flutters like a butterfly from bough to bough, peers with its bright eye into every cranny and crevice, hangs head downwards like the restless tits, and is generally so absorbed in its busy search, that it will allow the spectator to approach quite close without its testifying the slightest alarm. So fearless too is its disposition, thut I have several times approached within arm's length of it. During the severe weather which ushered in the year 1871, a little Gold-crest came to receive our bounty, and on one occasion fluttered down to my feet with the

greatest confidence and trust. When busily hunting for food among the boughs of the pine and the fir, the Gold-crest frequently repeats its shrill callnote, which closely resembles the sharp squeak of the Shrew. Its song proper is a sweet feeble little strain, consisting of a few short notes-tweetie, tweetie! ending in a long-drawn twee! This is repeated while the tiny performer is swaying about on the branches of the fir. It first begins to sing in February (in mild seasons in January) and on till August or September.

At the end of April or the beginning of May, the Gold-crest begins to exercise its skill as a designer and weaver, and in this accomplishment it has but three rivals among the British birds; viz., the Chaffinch, the Goldfinch, and the Long-tailed Tit. Early in May, 1868, I watched the progress of a

in the aviary. Bechstein, that great authority on such matters, says that the young Gold-crests may be easily reared if taken before they are fully fledged. He recommends as food, meal-worms cut small, flies, ants'-eggs, and wheaten bread soaked in milk: care must be taken to make the latter neither too stiff nor too moist. He also says that insect food is necessary to them and seeds injurious. These pretty little creatures live and thrive well in a warmed and ventilated greenhouse with a small pinetree in the centre, or a large cage in a moderately

warm room.

Kingston, Abingdon.

PARASITIC FLIES.

nest, which was built in a spruce-fir close to this BY this term I do not mean the hosts of black

house. Noticing the tiny builders flying about with materials in their bills, I watched them for some time, and at length discovered the nest at the extreme end of one of the fir boughs. The tiny owners worked most industriously, and in the space of a week the nest was completed, and two eggs laid. The nest hung between two small end boughs, to one of which it was attached by ropes of cocoonsilk, and the other was woven in with the materials of the nest. The nest was about four inches and 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 the opening. In this soft bed the eggs were laid, and from their diminutive size appeared almost lost among the feathers with which the hollow was so plentifully adorned. The eggs were of a delicate cream-colour, with a pale brown zone or band at the large end.

In June the Gold-crest brings out its little family into public life, and they hunt for food in company, resorting frequently in winter to the hawthorn hedges, and often collecting into flocks of some numbers. Selby affirms that this tiny creature sometimes migrates, and says that in October, 1822, after a very heavy gale and fog from the N.W., thousands of these birds were seen to arrive on the seashore and sandbanks of the Northumbrian coasts.

To conclude. Though not an advocate for keeping birds in confinement, having always preferred studying the really wild denizens of the woods and fields, yet in deference to those who hold a contrary opinion, I may as well give a few second-hand hints as to the management of these tiny creatures

flies, sand-flies, gnats, mosquitoes, et id genus omne, which try men's patience and temper by sucking their blood; but a still worse "crew," whose mission it is to deposit eggs either upon or within the human body. In these cases it is the larva or grub which works all the mischief. The period of occupancy occurs before the perfect insect comes to light; and therefore man's tenant, in the instances to which I allude, is the grub,-not the fly.

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The last place perhaps in which one would look for the larva of a flower-fly (I know no better way of rendering the technical name, Anthomyia) is the human stomach. Yet at least two species (scalaris and canicularis) occasionally occupy this singular locality. How can they get there? is the first and most natural question; but one which it is by no means easy to solve. The most probable suggestion is that they are introduced with vegetables which have been standing for some time, and on which the mother-fly has," in the innocence of her heart, laid a batch of eggs, unwitting of the evil consequences likely to follow. But in whatever way they have been brought into their temporary lodgings, they appear to adapt themselves readily to surrounding circumstances, and to make themselves quite at home, clinging to the inner surface of the intestine by means of minute spines with which the back and sides are armed. While there, they cause, as may be supposed, considerable irritation.

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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."

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

Fig. 31. Lucila hominivoras.

Fig. 32. Grub of ditto.

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.)

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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 gadfly, 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 operation, 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

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