Ix. 



dipterologist who found a considerable number of these flies flying 

 round the dead body of a roe and creeping into its coat. He 

 caught a series of them, which proved to be males and females. 

 The latter had cast off their wings in dying. In my experience 

 both sexes retain their wings until they have taken possession of 

 their host, and these are brushed off when creeping among the fur. 

 When I was tracing the distribution of the forest fly, Hippolosca 

 equina (which was said by a correspondent of the Field to be 

 restricted to the Hampshire basin, but which had to my knowledge a 

 much wider distribution), I took from my horse a fly allied to the 

 forest-fly, but wingless. The next day I captured several 

 more from among the hazel-bushes of the same wood, and 

 several afterwards flying about in the rides, but could keep 

 none of these incarnations of liberty alive more than a few 

 days. I gave the next batch a daily meal on one of my horses, 

 which quite succeeded, and before the end of October I found 

 I had about 100 pupse, which I kept in the skin of a deer. 

 At first the pupae were soft and of a pale colour. The head, which 

 was broad and flat, was furnished with two widely-distant eyes. 

 About the seventh day they cast their first case and became 

 invested in a horny boat-shaped case of a dark brown colour, 

 open at one end, and disclosing the head. The sides were keeled, 

 the upper surface had three prominent ridges, a characteristic 

 feature of the adult fly. After an interval of a fortnight another 

 moult took place, when the three ridges were replaced by six. 

 The pupae remained quiescent until August, when they again 

 began moulting. After every effort I was unable to procure their 

 development into the imago state, which I attribute to insufficient 

 food, supposing that, like the chrysalis, they did not require to 

 be fed. The complete history of the fly must remain unrecorded at 

 present. I hope to be more successful with those I have now under 

 treatment. Although the pupae are enclosed in a rigid horny 

 case, and have no outer limbs or apparent means of locomotion, 

 they have the power of moving freely to all parts of the vessel in 

 which they are confined. 



