THE BOT FLY.

Marlborough Express, Volume XXIX, Issue 23, 28 January 1893, Page 2

THE BOT FLY.

TO THE EDITOR.

Sib,— l take the following description of the " Bot Fly," which is attracting some attention just now, from the Frenoh naturalist, M. Louis Figuier'a "Insect World." It should be interesting and useful to stock-owners among your readers. " The genus iEstrus, the Gad, Bot Fly, or Breeze, says M. Figuier, comprises those formidable insects which attack the horse, the ex and sheep; (1) The Jistrus Equi or Gadfly (which attacks the horse). The head of this insect is large and obtuse; the face light yellow with whitish silky fur ; the eyes blackish ; the antennas ferruginous (rusty coloured) ; the thorax grey ; and the abdomen of a reddish yellow with black spots J the wings are whitish with a golden tint, and divided by a winding band of blackish colour; the feet are a pale yellow. Daring the summer months the iEstrua frequents pastures, and the female generally deposits her eggs on those parts of the horse's body which can be most easily touched with the tongue, that is, at the inner part of the knees or the shoulders, and rarely on the outer part of the mane. The eggs, wbioh are white and of conical form, adhere to the horse's hair. It often happens that from 400 to 500 eggs are deposited upon the same horse, and when licking himself the horse carries them into his mouth, and thence they enter the stomaoh, where they develop into larva of a reddish yellow colour. (2) The JSatras Bovia (bot fly) aas a very hairy body ; large head ; the face and forehead covered with light yellow hair; the eye 3 brown, und tha antennre black; the thorax yellow barred with black ; the abdomen of a greyish whita at the. base, covered with black hair on the third segment; and the remainder of an orange yellow; the winga are smoky brown. As soon as cattle are attacked, they may be seen, their heads and necks extended, their tails trembling and held m a line with the body, to rush to the nearest water. The eggs of this fly are deposited m the skin of the bullock, and those parts of the body m which the larv« exists are easily recognised, us above each larva may be seen a sort of tumor, termed a bot or bump. It is generally on young cows or young bullocks, from two to three years of age, that these tumors exist. They are rarely to be seen on old animals, the fly preferring those whose skin offers little resistance.

(3) Tbeteestrua ovis, or breeze fly of the sheep, has obtained notoriety on account of its attacking those animals. It has a less hairy head, but larger m proportion to the size of its body than the rostrus equi. Its face is reddish, the eyes are of a dark and changing green, the autenna black, the thorax brown sometimes grey bristling with small black tubercles, the abdomen white spotted with brown or black, the wings are hyaline (transparent green). It lays its eggs on the edges of the sheep's nostrils, and the lame lives m the frontal and maxillary tissue?. The worm is whitish, with black transverse band on each of its segments. Its head is armed with two horny black hooks, and underneath each segment of the body are rows of tubercles surmounted by small bristles having reddish points, and all of them bent backwards. At the sight of this fly the sheep feels the greatest terror. The animal that is attacked shakes its head when it feels the fly on its nostril, and strikes the ground violently with its forefeet. It then runs here and there holding its nose near the ground, smelling the grass and looking about anxiously to sse if it is still pursued." — I am, <&&of. f T. S. Grace, Archdeacon. Blenheim, January 26, 1893.

The most wonderful line of dress stuffs ever seen m Blenheim! We have fifty pieces of double-width all wool colored cashmeres that are honestly worth 2s 6d yard, we have decided to dear at Is yard. This line cost 2s m the warehouses, and requires to be seen to realise what a bargain it is. Be sure and call before it is too late, at B« Awdw'e, Market Street,