THE ENTOMOLOGIST.

Otago Witness, Issue 1903, 24 July 1890, Page 5

THE ENTOMOLOGIST.

(ESTRUS (GASTROJPHILO) EQUI. As this peHt of the borae iB now firmly established in the colony, some particulars of its life history may be acceptable and useful to those who use the servicoa of the noble animal. There has for a long time baen known to 'exist in New Zealand a fly of this genus, but ita identity with the above— that ia, with the English apeoies, known aa the common horsd bot fly— ia a question that was set at rest by the capture of the female of the English Bpeoieu in the aot of ovipoßition. This fly doea not alarm the horse, as many suppose— the fly from whose pursuit they dash with frantic haste iB of quite a different genus. Like the (Entrus bovis, it is a dipteron, or two winged fly, and it deposits ita eggs on the hairs of the horse in a position where the animal oan reaoh them with the tongue, generally on the ahoulder or knee. In doing this the female darta Bwiftly, but silently, down, # and deposits an egg ; quiokly recovering her position she remains a moment apparently motionless, and then again darts down and deposits another egg, and so on. These eggs resemble small elongated conon, the base being a Httle trap door, oloaed by a kind of hinge. They are attached by » fluid at the email end of the cone to the hair, the small end being towards the root of the hair, bo that when the horse lioks his tongue opena the lid and licka in the little maggot, whioh ia in an advanced etato when the egg, or box, is laid. The larvae is thus takon into the mouth, and the one in fifty of them that escapes the teeth is BWftllowed with the food, and to the walls of tbo Btomaob, from whose juices they derive their nourishment, and where they remain till they have passed the larvae Btage, when they loosen their hold and pass out with the excreta. They then creep into Borne crevice, or under some stone, and pass into the pupa stage. The method of breathing in the foul air of the horse's stomach ib curious and interesting ; but tho description is technioal, and would occupy much space. This fly is not by any means bo injurious as the CE. bovis. Old style veterinariea will even say a few larvro cause healthy stimulations, but this ia not bo, and a great many would most 'certainly affect the horse's health- The best thing to use is a rap smeared with an emulsion of kerosene and oil (1 to 16, mixed by the introduction of a little snap— Boap and water boiled together firat). It is better as a preventive than a euro, aa the horse, generally licka them in soon after they are laid, and it is not oasy to tell when the cases are empty. Sometimes the Blight sensation of the fixing of the egg will cause the horse to lick, but, curiously enougb, it ib generally brought about by an intermeddling fly of a totally different speoies, which lights on the parts and irntateß 4he horse. Hens will dispose of the maggots in stable-fed horseß* dung, and should have access to the Btablea. Entomologist.