XII.— Gathering CantViarides.

The SiyhpidcB, for which Kirby,* in 181 1, instituted a distinct Order, which he called Strepsiptera, in allusion to the contortion of the elytra, and to which Latreille f subsequently applied the name of Rhiptptera^ are, perhaps, the most anomalous of all insects. Great diversity of opinion has existed respecting their affinities; but modern systematists, with but few exceptions, concur in referring them to the

Order Coleoptera, and locating them in proximity to Melo'e. In the larva state, all the known species of the family inhabit the bodies of hymenopterous insects of the genera Andrena, Polistes, &c., in this particular resembling the dipterous genus Conops, which inhabits the body of humble bees,:|: and apparently in no way inconveniencing their victims; a fact which has been accounted for on the supposition that their existence in the larva state is but short, and that their attacks being directed against the abdomen, and not the thorax, the seat of life in insects, their presence does not affect the activity of the victim. The larva has a soft fusiform body, surmounted by a somewhat globose head. While feeding, the head is towards the base of the abdomen; but on changing to a pupa, this position is reversed, and the head — at first of light brown, but which after a short time becomes black — thrust out between the plates of the abdomen.

The imagos, which are of small size, namely, about the eighth of an inch long, are found during May and June. They have four wings, but the anterior pair, of hard texture, somewhat resembling elytra, but hardly answering to them in structure, are very poorly developed, and curled round the front pair of legs, hence the name bestowed, by Kirby, from (rrpexpcns, a twisting, and irrfpSu, a wing; the posterior wings are fully developed, and fold up like a fan, whence the Order received the name of Rhipiptera from Latreille. The eyes, the facettes of which are few in number, are placed on a foot-stalk, whence the name of the genus Sty/ops. The parts of the mouth connect the Strepsiptera with the mandibulated insects, although by some supposed to bear analogy by their functions to those parts in the Diptera. The male only is winged; the female is very like an apodal larva, the larva being an active hexapod.

The family Stylopidce is divided into four genera, of which two only, Xenos and Stylops, were described by Kirby in the essay referred to above. First, Xenos ^ from |eVos, a guest, the most prolific in species, ' of which Xenos Rossii^ sometimes called vesparum^ may be taken as

" On a new Order of Insects," Linn. Trans., vol. xi. f In Cuvier, " Le Regne Animal," ed. i., tome iii., p. 584. + See p. 69.

the type. Secondly, Elenchus^ of which Elenchus Walkeri is the type. Thirdly, Sty lops (Fig. 543), parasitical on various species of Andrencey of which Stylops MelittcB^ having a fleshy abdomen and the wings longer than the body, may be considered typical: and lastly, Halidophagits^ of which only one species, infesting Halictus

ceratus,'^ named Halictophagtcs Curtisii^ is known to exist, and which makes its appearance inthe month of August. These singular insects are found in various parts of the world — Europe, Aus-

Fig. 543- -Stylops (magnified). ^^^^^^^ ^^^^ America. They were discovered by Professor Peck almost simultaneously with Mr. Kirby's discovery in England, to whom he sent specimens of a species which has received the name of Xenos Peckii in New Zealand and elsewhere. Siebold, in 1843, having obtained some eggs, was able to observe the larvae, and he soon discovered that the females of Stylops, one of the Strepsiptera, were blind, had no legs, and always retained the appearance of larvae, and that they never quitted the bodies of those insects, in which they pass a parasitic existence. George Newport paid great attention to the history of these curious insects, and when he wrote his article, '' Insecta," in the ''Cyclopaedia of Anatomy and Physiology," four distinct genera of these minute parasites had already been discovered. One of the largest species {Stylops Speiicii) is scarcely more than two lines in length, while the smallest species yet known is not more than two-thirds of a line, or scarcely a line in breadth with its wings expanded. They undergo metamorphosis \ and the males, when they have become perfect insects, fly and roam about, but the females are condemned to a perfectly quiet life. The head and the thoracic segments of the bodies of these last are united completely, but the abdomen, which is very large, always remains soft, so that the whole of the body only appears to be formed of two portions. They are ovo-viviparous insects, and the young larvae escape as such from the body of the mother. They are active creatures, and, being furnished with long legs, crawl over the hairs and skin of the hymenopterous insect they are parasitic upon. They behave like the larvae of Meloe and Sitaris, whose peculiar methods of life have been noticed in our description of these coleoptera.

Clinging on to a wasp or a bee, they are carried ofl", and finally

Halictus and Andrena are two genera of Bees.

COLE.OPTERA. 305

arrive in the nest or hive, as the case may be, and there they attack the larvcX. When once fixed upon the hymenopterous larvse, they undergo a change of skin, and their shape then becomes totally

Fig 544.— Female and Larva of Stylops.

different, and their legs are atrophied. But these parasites being exceedingly small, do not kill the larvae; they suck their juices, after he manner of the Ichneumons, and do not interfere with the meta- Qorphoses of the insects upon which they are parasitic. On the ight hand, in the accompanying engraving (Fig. 544), there is a larva

much magnified, lately born, and climbing upon the hair of one of the Hymenoptera, and on the left hand there is a perfect female insect, very much magnified, with ovo-viviparous larvae within its abdomen, and between the two figures there is a representation of a larva of the natural size. It is evident, however, that ova may be expelled from the mother before they are hatched.

Packard describes the curious history of the female Stylops, which he found parasitic on one of the bees. He caught the bee, and on examining it he noticed a pale reddish-brown triangular mark on the abdomen, and this was the flattened head and thorax of a female Stylops. The creature is included in the body of the bee, and is nourished by its juices. The head and thorax of the parasite were noticed to be soldered into a single flattened mass, the baggy hind body being greatly enlarged, like that of the female white ant On carefully drawing out the whole body from the bee the mass was found to be very extensible, soft, and baggy, and on examining it under a high power of the microscope, multitudes of very minute larvae were observed, and they began to issue out from the body of the parent all alive, and not as eggs. The male of this Stylops childretn is totally unlike its partner, having large hind wings, and being able to fly, as has already been noticed. It appears, then, that the larvne are hatched or crawl out of the body of the mother on to the body of the bee, and are then transported to its nest; then they enter the body of the bee larva, and live upon its fatty matter. The male Stylops is turned into a pupa within the bee, and so is the female;

but after the second metamorphosis the male flies off", leaving his wingless partner imprisoned for life, and she usually dies immediately after giving birth to her myriad offspring (Packard). The female respires by peculiarly arranged tracheae, and absorbs nourishment through her skin as well as by means of an alimentary canal, which ends in a blind sac. All the beauties of the female, so far as they are visible to the male, consist in the tiny patch which appears just without the body of the unfortunate bee, and the ova collect in a space which opens between the united head and body and the abdomen.

The genus Mylabris corresponds most in structure, in appearance, and in properties, to Cantharis, whose place they take in the East, in China, and in the south of Europe. They are found in chisters on the flowers of chicory, thistles, &c. The Mylahis chicorii, common enough in France, especially in the south, is of small size, whilst the other species are rather large. It is black, hairy, with a lai^ge yellowish spot at the base of each elytron, and two transverse band^ of the same colour,

COLEOPTERA. 507 Another genus of this family is Meloe, with very short elytra, and jvithout wings. They walk slowly and with difficulty on low plants, the female dragging along an enormous abdomen tilled with eggs, rhey are generally observed in spring. In Germany they give them the name of Makvurm (Mayworm). Their succulence would expose them, without doubt, to the voracity of birds and of insect-eating Mamraifers if they had not the power of exuding at will, in the moment of danger, from all their articulations, an unctuous humour

F'g- 545- — Sitaris humeralis. Fig. 546. — First larva of Sitaris humeralis (magnified).

a reddish-yellow colour, the odour and probably also the caustic properties of which repel the aggressor. The females lay their eggs underground, and out of these come forth larvae of a strange shape. Swallowed by cattle, they cause them to swell and die. It is for this reason that Latreille has given it as his opinion that these insects are the Buprestis of the ancients, of which the law of Cornelius speaks, " Lex Cornelia de sicariis et veneficis." But the name of Buprestis was applied by Linnaeus to a genus of which we shall treat farther on, and it has been generally adopted by naturalists.

The commonest among the Meloes is the Meloe proscarah(Eiis, which is to be found in abundance, in the month of April, in the meadows near the bridge of Ivry in the environs of Paris. The metamorphoses of the insects of this family had remained for a long

time surrounded with an impenetrable veil of mystery, but the researches of Newport in England, and of M. Fabre (of Avignon) ir France, brought to light several extremely curious phases, undei

which are accomplished the metamorphoses of the Melo'e cicatricosiis and of the Sitaris hwneralis, a species which belongs to the samt family.* These observations, of which we are about to give a rapic summary, will probably help towards unravelling the first states o: Cantharis. The Sitaris hiimeralis (Fig. 545) takes no nourishment wher arrived at the perfect state. When the female has been impregnated she lays at the entrance of the nest of a solitary bee from 2,000 tc 3,000 small whitish eggs, stuck together in shapeless masses, month afterwards there come out of these eggs very small larvae, o a shiny dark green, hard-skinned, armed with strong jaws, and lont

Fig- 547' — Pseudo-nymph Fig. 548.— Third larva of Sitaris Fig. 549. — Pupa of Sitari: of Sitaris humeralis. hunieraUs. humeralis.

legs and antennae (Fig. 546). These are the first larvae. They remair motionless, and without taking food, till the following spring. A this period are hatched the male bees, which precede the appearance of the females by a month. As the bees come out of their nests these larvae hook themselves on to their hairs, and pass then to the- females, at the coupling period. When the male beef have built the cells, and furnished them with honey, the female, aj we know, deposits in each an egg. Immediately the larvae of the Sitari. let themselves fall on these eggs, open them, and suck their contents Then they change their skin, and the second larva appears. Thi^ one gets into the honey, on which it feeds for six weeks. It is blind whereas the first larva was provided with four eyes, no doubt tc enable it to see the bees which were to serve as its conductors, in like

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