Exhihifs. 



The President, Mr. Sheldon, and Mr. Adkin all brouglit 

 for exhibition some remarkable series of Cidaria truncata, 

 C. citrata and C concinnata. 



A British Sawfly. — The Rev. F. D. Morice made the 

 following communication. 



On July 21, 1921 I received from Miss E. Chawner, F.E.S., 

 some cocoons formed by larvae of Pristiphora pallipes Lep., 

 one of several sawflies which are specially attached to the 

 gooseberry. She had obtained them from eggs laid in captivity 

 on leaves of the food-plant by an unfertilised $, so that the 

 whole brood was "parthenogenetic." From some of these 

 cocoons imagines — all ?$ — emerged during their journey from 

 Lyndhurst to Woking. I placed them at once with some 

 cuttings from my own gooseberry bushes in a glass-covered 

 tin, and very soon saw them beginning to lay eggs. Six days 

 later (July 27) the eggs had produced young larvae, which fed 

 up very rapidly, and by Aug. 7 had almost all s|)un up either 

 at the bottom of the tin or between leaves of the food-plant. 

 In 6 more days, viz. on Aug. 13, irnagines (again all ?$) began 

 to issue from the cocoons, and lay eggs, from which I obtained 

 another lot of larvae, which may or may not produce imagines 

 next spring. 



Hartig has estimated the average duration of a sawfly's life 

 from leaving the egg to emergence as an imago as follows : — 

 1| to 2 months from leaving the egg to forming the cocoon, 

 10 days to 3 years from forming the cocoon to pupation, 

 8 to 14 days from pupation to emergence. 

 I cannot find that he gives any figures about the time spent 

 in the egg-stage. But leaving this out of account, it would 

 seem that on his estimate the minimuni time which the develop- 

 ment of my insects from egg to imago ought to have occupied 

 would be 63 days and the maximum 1,169 days. The time 

 which it actually took, exclusive of 6 days spent by them as 

 eggs, was 11 days as larvae feeding, and 6 in the cocoon — 

 17 days in all ! 



I suppose that this extraordinary hastening of the process was 

 connected in some way with the exceptional heat and drought 

 of last summer. But I do not think that these conditions can 



