53 



no indications that this is so, and it is almost certain that the whole 

 is stored up until just after the final change of form. The 

 porcellaneous coating to the mass is, in our opinion, homologous with 

 the milky or chalky fluid ejected by a moth or butterfly on emerg- 

 ence, and is composed of urates, etc., formed as a waste product 

 during the profound metabolic changes that have been taking place 

 during the pupal and late larval stages. 



Another interesting feature of the ant-lion that we wished to 

 investigate was the odour said to be emitted by the perfect insect. 

 This we were able to confirm, but the odour is faint, and not 

 constant; it is most readily perceptible after the fly has been 

 indulging in violent exercise, and is most strongly developed in the 

 male. In the females we could not always agree whether it was 

 present or not. This odour has been said to resemble that of ants 

 (formic acid?) and to be derived probably from the ants upon which 

 the larva has fed ; bat we found that it was present in a like degree 

 in flies bred from larvae that we had had in captivity for more than 

 a year, during which time they had been fed mainly on caterpillars, 

 and had certainly never tasted ants. The odour was clearly not 

 that of formic acid, but it is difficult to say what it does resemble. 

 It will be recalled that a fairly strong odour is also emitted by 

 the lace-wing fly, a near relative of the ant-lion, but no one has 

 suggested that l:his is the odour of the aphides on which the larva 

 has fed. 



Finally, we may mention one other object of our excursion, and 

 one with which we had no success. This was to obtain the early 

 stages of Ascala/)Jnti<. A. cocrcijus was common enough in some of 

 the Alpine meadows, but we were totally unsuccessful in obtaining 

 the ova, larv^e or pupae, either in their natural haunts or from living 

 specimens that we brought home. We hope to investigate this 

 matter further in the coming season, and if any Member will, help 

 us to obtain the requisite material, we shall be most deeply gi'ateful. 



