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82 naked shins, was enough to establish a decided "funk."

These and other hedgehogs which I have kept, at length got away, which, however well they are treated, they always endeavour to do; in one case (in as far as I could make out) falling over a ten-foot wall into a river; and as I have occasionally found them quite well at the bottoms of deep stone quarries, I presume that their peculiar dermal armature, or their ball-shape, when coiled up, renders a fall innoccuous.

I have penned these remarks in the hope that other observers might be enabled to say something in favour of my pet; for, as he has ever appeared to me not only harmless, but most useful as a destroyer of insects, I shall be glas, if possible, if, unlike usual gossip, may tend to save a reputation, and so preserve a race. , F.L.S., &c.

THE COMMON HOUSE-FLY.

ANY naturalists of considerable repute have not thought it beneath them to study and write the life and instincts of this insect. Notwithstanding

having made the little creature my particular study since last summer twelve months, it still remains a problem with me which is the common house-fly.

Out of the numerous flies which are frolicing about my parlour, I have caught three, which are now under the dissecting knife, two females and one male; the two females are to all appearance under the microscope exactly alike in size and markings, the same proboscis, brain, feet, spiracles, tracheæ, ovipositor and position of

the ova in the abdomen; but the material difference is, that the so-called house-fly is oviparous, and its congener ovoviviparous. We will, for distinction, call the house-fly number one, its congener number two, and the male number three: the ova of number one is smooth and rather a long oval, requiring several days to hatch, brings forth a maggot common in appearance to that species (see figs. 1 and 2), while number two brings forth its ova with the grub alive, perfectly formed, and very lively; the egg is somewhat obtuse, and partakes of a peculiar form, similar to two lappets thrown back, which gives a thick appearance on the sides, while the centre, which is beautifully honeycombed, is quite transparent; the opening is at the top, very simple, something like a purse, through which the grub passed in less than two minutes after the egg had been deposited. I had previously covered the ova with a drop of water to keep it moist, but it did not impede the little creature's progress in its endeavour to escape. Figs. 3 and 4 will give the exact drawing

of the ova and insect. I thought it worth while to call a witness to its faithful representation, as I had not at that moment an opportunity of mounting it as a microscopic object; the grub resembled more the caterpillar tribe, and certainly was a beautiful little creature, so perfect in its form though so minute. I will briefly give a description of the insect: the trunk or proboscis appears like two tubes attached together, at the bottom of which are two immature eyes; the tracheæ and spiracles were very distinct; it has ten legs on each side, fleshy and covered with hair; the body is covered with delicate spots and minute hairs, with ten fine horizontal lines of division formfrom [sic] top to bottom; the tail horn-shaped and fleshy. I have been rather particular in my description, because it differs so widely from anything of the kind I have ever met with.

The male fly, number three, is not, I apprehend, the mate of either of the two females from the dissimilarity of the proboscis (see figs. 5 and 6); in all other respects the male appears the same species, only smaller, which is the case generally. But I am at a loss to find a mate for the male fly; in this I may perhaps succeed in time. The number of female flies in comparison with the males of the so-