A. Iv Camkhon 61 



made for them with the point of a needle tliey achieved no ])rogre88 

 and finally died in al)ont an hour and a half. 



(2) A lar\a in its second sta<ie was similarly treated. After moving 

 about actively for about a (juarter of an hour, it seemed to find a spot 

 to its liking. Working vigorously it first made a small slit in the epi- 

 derm which it enlarged to a circular aperture by an unflagging series 

 of to and fro, semi-rotatory movements of its mouth hooks. In two 

 hours and twenty minutes it had disappeared completely from view 

 in the gallery which it had eaten out. 



(3) A larva of the third stadium, recently moulted, accomplished 

 the same performance in the comparatively short space of twenty-five 

 minutes. 



The pupal stage extends over a period of about two or three weeks, 

 and sometimes longer. Nordlinger (1885) believes the pupal stage 

 occupies fourteen days, whilst Taschenberg (1880) gives as low an esti- 

 mate as ten days, which is in accord with the ten to twelve days cited 

 by Jablonowski (1905). The insects hibernate in the soil as puparia. 

 Several larvae, collected during October, assumed the resting condition 

 on the 20th of this month, and from one of the puparia which were kept 

 amongst damp sand in a cool-house, an adult emerged on May 24th 

 of the following year, representing the elapse of one hundred and four- 

 teen days. 



The adult period, length of life-cycle. 



When the fly is ready to emerge it bursts open the retaining pupa-case 

 anteriorly by means of the pressure of the exserted ptilinum and makes 

 its exit through the resulting T-shaped cleavage. The animal does not 

 at once assume its final, natural colour. The thorax is pale, cinereous, 

 whilst the legs and abdomen are pale yellowish. Having finally rid 

 itself of the puparium, the imago remains resting for a time during which 

 the ptilinum is periodically inflated. This action together with a 

 peristaltic movement of the abdomen, is associated with an apparent 

 growth in size of the fly and also with the expansion of the wings hitherto 

 neatly folded up and closely applied to the body. The wings take 

 about three minutes to expand completely, the extremities unfolding 

 first. All the time the colour is becoming darker. 



There is then a period of apparent rest when the various regions 

 of the body assume their normal shape, and the cuticle hardens. The 

 wings are slightly raised and become more transparent. The frontal 



