BY GERALD F. HILL. 767 



complete the cycle. The periods occupied by the different stages 

 were not accurately noted in any of the above rearings, but, 

 from other observations under varying conditions, it was found 

 to be as follows — egg-stage, 18-20 hours ; larval stage, from 

 liatching of egg to the formation of the puparium, 72-96 hours^ 

 pupal stage, 72-120 hours. 



Courting takes place on the host, but the process of mating 

 has not been observed, either upon the host or elsewhere. The 

 position of the Hy while resting or feeding upon the host is 

 usually that with the body vertical and the head downward. 

 During courtship, this position is maintained by one sex, the 

 othei- occupying a vertical position with the head directed 

 upwards. The wings of both are kept in constant vibration until 

 the pair leave the host, presumably to couple. 



During the heat of the day and at night, the majority of the 

 Hies rest upon the flanks and withers of horses, and about the 

 horns of cattle. 



Xahiral Enemips. — Few indigenous birds gather their food in 

 dung; it is improbable, therefore, that dung-breeding flies and 

 other insects ai-e preyed upon in their earlier stages by these 

 agents. The imagines of Lyperosia, like those of other flies, are 

 preyed upon to some extent by Fantails [Bhipidura bicolor), 

 which follow and rest upon the backs of stock. 



In.sect-predators play a more important part in the control of 

 of this pest, but it is not believed to be considerable. The 

 recently deposited eggs are gathered by certain species of ants 

 for food, amongst which the following species may be mentioned 

 — Solenopsis germinata F., var. rufa Snd., Iridomyrmex detectiis 

 Smith, and Odontomachus ruficeps Sm., var. acufidens Forel. A 

 more important enemy is a small Hymenopteron (Sericophoriis 

 rducens Sm.) which captures the flies while feeding or at rest. 



Methods of Control. — The flies are naturally bush-insects, 

 breeding, for the most part, in the fresh droppings of cattle and 

 buffaloes. Accumulations of stable-manure and litter do not 

 attract them, noi' do they breed up in numbers if fly-infested 



