230 Agricultural Gazette of N.S.W. [J/r/r. 2. IflOS. 



an ulcerated fester. The e^g.s of some species that attack the smaller and 

 softer-sUinned animals simply hatch where tliey are deposited, and th(^ iipiiute 

 larva^ pierce the skin, forming the warble beneath. 



The sheep-Hv {<Et-trus oris) lays its eggs in the nostrils of tlie unfortunate 

 sheep, from whence the larvje make their way through the mucus of the 

 nasal passages. The sheep, when badly infested, develop a disease kiit)\\n as 

 " stairsprs," which sometimes kills numbers. 



Many animals appear to l)e infested witlt theii- own particular species ; 

 there are about ten species known in England which infest the horse, ox, ass, 

 sheep, and red deer. The camel in Arabia is infested with a lai'ge species 

 {Cepha/oittijid jiificnlata), and as Mr. Tepper has recorded the finding of some 

 large bot-larva' in South Australia, said to have come from the camels, it is 

 probable that it has been inti'oduced into those (bsti'icts of Australia wlieie 

 camels are us^ed for carrying. Even the smallest animal has its parasite, for 

 at a meeting of the Entomological. Society in 1888, Mr. C. O. Waterhouse 

 exhibited the larva^ of an (Entrus which measured neai'ly an inch and a half 

 in length, and was found in the body of a common mouse from Peru, of which 

 it occupied almost the whole of one side. 



The true bot-flies belong to the genus Gastero/jJiihifi, and the common 

 species is known as the horse-bot {Gastei-ophilus equi) ; it was recorded in 

 Victoria a good many years ago. There may be several species in Australia. 

 Kirk,* writing of the pest in New Zealand, says : "There seems little doubt 

 that we have at least two, if not three, species of horse-bot in this Colony ; 

 but that common in the North Island is, undoubtedly, UnsteropliUns pqui, a 

 comparison of New Zealanil specimens with types received from England 

 revealing no dift'erenee whatever."' Tiiis species has a very wide range over 

 Europe and North America, and was introducul into New Zealand many 

 years ago, and was also recorded from ^"ictoria some time befoi-e it was 

 observed in this Colony. 



Naturally, it is very easy f<ir these flies to be introduced into a clean 

 country in the lai-val state while infesting imported animals; and though I 

 understand that the droppings of all stock in i[uarantine are burnt, some may 

 be voided after the animals have finished the regular time of detention. I 

 have recently had samples of bots from Fiji, said to have been introduced 

 with mules from America, which is a (liferent species to the common one in 

 Australia. 



Though there is no doubt about the damage that the ^\al■ble Hies of the 

 cattle and the nasal-flies of the sheep do to the animals they infest, there is a 

 great diversity of opinion as to the eftVcts of bot-flies in the internal organs 

 of the horse ; some authors even assert that their presence does not hurt the 

 animal at all, but rather has a beneficial effect. Bracey Clark, who published 

 a treatise on these flies in 1790, f was of this opinion, and also the well-known 

 naturalist, Reaumur. A'all snieti, however, attributed to this cause an 



* "Leaflets for Farmers," No. 19, 1895. T. W. Kirk, Department Agriculture, 

 New Zealand. 



t Trans. Linnean Society, Vol. Ill, 179(1. 



