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When fullgrown, the larva breaks through the tumour, and slides down to the ground iii the cool of the morning: it there digs itself a burrow, into which it retires. The larva skin. becomes hard, and turns to a kind of solid shell, En this case the insect is transformed to a chrysalis, and afterwards o a winged fly. it would be almost impossible for the fly to escape from this strong enclosure, had not Na hire made a curious provision fir' the purpose, there being a small valve at one end, ft stoned. only by a very slight filament, which, on the first push made by the (ad ily, opens without Eli fliculty

The difiircnt kinds of animals are attacked by distinct species of the Gad4ly. That which farriers call .Jots, is peculiar to the Horse The precaution of the parcit it scct for the future wclfhre of hvr young, deserves a minute account. When she has fixed upon a horse $uited to her purpose, she approaches it on th

in g, and holding hs'cu inwards, she

h'pcnds herself for a few seconds in that posi lion, then suddenly darts upon the selected spot, and leaves her egg adhering to the hair, to which it is fastened by a glutinous liquor. This is repeated by a number of flies, till four o five hundred eggs arc sometimes placed on

one