reared four of these curious flies from humble-bees which he

had placed in a box.

There are several species of Conops, all prettily coloured.

There is, for example, Conops fiavipes, a smaller and slighter insect tlian the preceding species, velvet-black in colour, banded with bright golden yellow. Then there is Conops rufipeSf which is coloured exactly like the hornet, the thorax being reddish-brown and the abdomen yellow, banded with dark brown. Another species, Conops macrocephalus, is shown on Woodcut FIs’* 2, and the curious abdomen of the male insect is drawn at Fig. c. The speciflc name macrocephalus signifles long-headed, and is given to the insect in consequence of the shape of the head, which is wider than the thorax.

This is a pretty and not common insect. The general colour is black, and there is a coating of short ashen hairs. The face is yellow, the antennae rust-red, and upon the shoulder of the thorax there is a spot of silvery white. The wings are yellowish, darkening into brown on the costal margin. The abdomen is black, the margin of each segment is yellow, with a silvery gloss. The legs are reddish, and the base of the thighs dark brown. The insect may be found upon flowers.

The generic name Conops is clearly a wrong one, and calculated to mislead anyone who is something of a classical scholar and little of an entomologist. The word is Greek, signifying a gnat, and has been incorporated in our language in the well-known word ‘ canopy,’ i.e., a gnat-curtain, that being the real meaning of the word. Herodotus employs the word Conops when describing the gnats or mosquitos which infest the marshy lands on the banks of the Nile, and the method employed by the fishermen in guarding themselves fiom the attacks of these troublesome insects.

We now come to the enormous family of the Muscid®, a family which may rank with the ichneumon-flies, the Noctuse and Tineae Moths, and the Eove-beetles, as tests of an entomologist’s temper and patience. It is hardly possible to imagine anything more trying to the entomologist s s 2 than to have half a

dozen large boxes of Muscidao placed before him, -with instructions to find out their names, and to marshal them in their right places. The task really seems to be a hopeless one, and life to be too short for accomplishing it, more especially as there are sure to be some hitherto undescribed species, and they are equally sure to come first to hand, as if for the express purpose of making the unfortunate entomologist hunt for their description in vain. At least a thousand species of Muscidae are known to inhabit England, and it is probable that twice that number may be yet discovered and named.

Fortunately, there is no difficidty in deciding whether a fly belongs to this family or not, as a glance at the proboscis will at once determine its place. This organ is short and membranous, and terminated by two large lobes, the structure of which will be briefly described in the course of the following pages. None of the Muscidse are of any great size, the ordinary house-fly being of about the average dimensions.

Without going further into detail, we will begin with the insect which is represented on Woodcut LXXIII. Fig. 3, and which is called Tachina ferox.

In some respects this insect resembles the ichneumon-flies which have been already described. The female lays her eggs upon the bodies of various caterpillars, and the young larvae, as soon as they are hatched, penetrate into the body of the caterpillar, and feed upon the fatty substance which was intended to be the subsistence of the insect during its pupal stage of existence. One naturalist reared as many as eighty specimens of Tachina from a single caterpillar of the Death’s-head Moth. Not only the Lepidoptera, but other orders of insects, are subject to the attacks of these flies, for they have been ascertained to inhabit the larv® of various Coleoptera, Hymenoptera, and even the bodies of spiders.

The present species has its head tinged with grey, and chestnut hairs on either side. The abdomen is yellowish, and shining as if made of horn, and is black along the middle, and slightly clothed with stiff hairs. The wings are transparent, and tend to yellow towards the base.

The largest of these insects is that which is drawn on Woodcut LXXIII. Fig. 4. It is called Tachina grossa, and is so

large and hairy that it looks very much like a black humblebee. The general colour of this insect is black, but there is

some yellow hair on the face and sides. The very peculiar

antenna is shown at Fig. 6, and the front of the head at Fig. a. Altogether no less than one hundred and sixty-six species of Tachina have been discovered in this country, and described ; and, in all probability, many more remain to be discovered.

Musca or Anthomyia lardaria, female, a. Do., antenna. 6. Do., foot. c. Do., facets of eye. 2. Musca d. Musca cMoris, head of female. chloris, male, e. Do., tongue. /. Do., antenna.

Another figure of Tackma grossa is given on Plate XX Fig. 4.

On Woodcut LXXIV. Fig. 1 is shown an insect called the Meat-fly {Musca Anthomyia or Ancia lardaHa) In this genus the bristle of the antennae is feathered, the abdomen IS oval and bristly, and the alulets are large. The colour of

this species is blue-black, and the head is gilded above and in front. The eyes are hairy, there are four longitudinal black stripes on the thorax, and the whole of the body is sparingly covered with very short greyish down.

There are many species of this genus, the larvae of which undergo their transformation in various substances, both animal and vegetable. These substances are generally in a more or less decaying state, but there are some species which make their larval home in the roots of different plants, the radish and the onion being particularly favoured by them.

The last-mentioned insect, Anthomyia ceparuniy lays her eggs close to the ground, sheltered by the leaf-sheath. Thus protected, the larva is soon hatched, burrows downwards into the very heart of the bulb, and very effectually destroys it. Then there is the Lettuce-fly {Anthomyia lactucce), which biurows into the heart of the lettuce, as it is tied up for the purpose of blanching the leaves ; and the Cabbage-fly {Anthomyia brassicce), which performs a similar task with regard to the cabbage, choosing for its depredations the junction of the stem and leaves.

The second species on Woodcut LXXIV. is called Musca chloris, and the two are introduced so as to show the construction of the most conspicuous parts of these insects.

On account of its colour, this insect is sometimes called the Geeen-bottle, in contradistinction to the Blue-bottle. Its colour is bright shining green, slightly inclining to blue, or taking a golden gloss. There is a black stripe upon the crown of the head. The eyes are brownish-red, and are divided in the female by a broad band, and in the males by a narrow one. The name chloris is Greek, and signifies green. The insect is tolerably common, and is very active and quick on the wing, so that it is not easily caught.

Fig. a shows the antenna of Anthomyia, the very long and cylindrical third joint being armed with a feathered almost Fig. c shows in outline five of the facets which go to bristle. up the compound eye of the insect. If dissected, this make wonderful structure, each of the facets being is shown to be a very then seen to be the termination of a separate eye. Every one of these facets is set, so to speak, in a frame, which is, part, hexagonal, like a honeycomb, but at the for the most

edges becomes either pentagonal or even square. It consists of a conical transparent body, called the cone, which is set in a layer of dark red pigment. If a fly be crushed, this pigment escapes, and looks just like blood. Then follows the ‘rod,’ a delicate fibre which connects the cone with nerve-centres in the head.

The whole of this structure has been thoroughly worked out by Mr. B. T. Lowne in his valuable monograph on ‘ The Anatomy and Physiology of the Blow-Fly,’ a work which every entomologist ought to possess, as the information which it gives does not merely relate to the particular insect of which the author treats, but explains the structure of various other insects. Having myself dissected great numbers of Blow-Flies, I am qualified to express an opinion on the subject, and to appreciate the careful pains and labour that the author has bestowed upon his investigations.

At Fig. b is given an outline drawing of the foot, with its two pads. The structure of this member has already been described, so that we need not refer to it again. At Fig. e is given a side view of the proboscis, showing its right lobe. This instrument forms a most beautiful object in the microscope. The two lobes are then seen to be traversed by a number of air-tubes of a rather peculiar structure, all radiating from two principal tubes, one to each lobe.

Generally the air-tubes or tracheae of insects are kept in shape by a spiral thread between the two layers of which they are composed, but in the air-tubes of the proboscis the place of the spiral thread is taken by a number of incomplete rings, called false tracheae. These incomplete rings look something like the ancient torque, or, to speak more familiarly, like a horse-shoe. The open part of each ring is downward, and the result of this structure is that they form a sort of strainer through which the Liquid portions of their food are passed. The shape of this curious organ is greatly varied, and although the proboscis of every Fly agrees in the principles of its construction, there are not any two species which have it exactly alike.

Fut^r ^ Woodcut LXXV. is shown the common Hotjse- Fly (^Musca domeshca), shghtly magnified. In all the insects belonging to this genus, the transformation is conducted in

much tlie same manner. When the larva is full-fed, the skin hardens into an oval cocoon, and the pupa is thus developed within its original larval skin.

To this enormous group belongs the Blow-Fly or Blue-bottle {Musca uom-itoria), which is so very familiar in our houses, and is so apt to deposit its eggs upon meat that even approaches decomposition. Here I may mention that the oval meat-safes, like dish-covers, which are so largely sold for the purpose of keeping the Blow-Flies from the meat, do entirely exclude the Flies, hut they do not exclude the eggs, so that the cook who has covered the meat carefully with one of these safes, often finds that, in spite of her precautions, the meat is as ‘ fly-blown ’ as if it had been totally exposed to the Blue-bottles. The fact is, when the mother insect finds that she cannot gain actual access to the meat, she goes to the top of the cover, and lets her eggs drop through the meshes of the wire gauze.

Then there is another insect, popularly called the Flesh-Fly or the Baker (iifwsca or Sarcophaga carnaria), which proceeds in a different and more expeditious way. With the Blue-hottle the eggs have to be hatched after they are deposited, but with the Flesh-Fly they are deposited as maggots, being hatched within the body of the parent. If the female be dissected before she has deposited her young, a most curious spectacle is disclosed. The abdomen is almost entirely filled with two white rolls, like riband, and when these rolls are examined with the microscope, they are seen to consist of a vast number of tiny maggots, placed side by side in perfect order. Each of these rolls contains from eight to ten thousand larvae ; and the reader may easily imagine how rapid is the demolition of the substances on which one of these Flies deposits her multitudinous young.

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