1900.] 



195 



4 to 7 p.m. Stray specimens may appear as early as 7 a.m. or as late 

 as 10 p.m., but I have never known one emerge during the rest of the 

 twenty-four hours, i. e., between 10 p.m. and 7 a.m. They often sit 

 on the top of one of the cases. The boxes containing the cases should 

 therefore be examined frequently during the day if the collector 

 desires good specimens for his cabinet. As a proof of this I may 

 mention that out of nineteen P. villosella, ^, bred this season, only 

 two were rubbed, and one of those came out during the journey from 

 Bournemouth. 



After I had bred seven or eight specimens there came out two or 

 three cripples. Thinking that possibly the pupae had got a bit too 

 dry, I laid the cases for a night in an ordinary damping box, with the 

 result that the remainder came out all right. The above remarks 

 apply, I believe, also to P. opocella, but I have not had so many 

 opportunities of observing its habits. 



With regard to the females the difficulties are entirely different. 

 They obviously cannot get rubbed, but how are they to be preserved ? 

 When Mr. Barrett was preparing his paper on this genus in 1894, he 

 told me that he had not been able to find a single specimen of P. 

 villoselJa, ? , in any collection from which it was possible to make a 

 description. Last year, with the aid of information kindly given me 

 by Dr. Sorby, F.E.S., I made some experiments, which seemed quite 

 successful, but I did not like to say anything about it until I was able 

 to compare the " perfect " insects then preserved with fresh specimens, 

 and I am now able to say that the usual 4 per cent, solution of 

 Formalin gives a result which is perfectly satisfactory, the insects re- 

 taining both shape, size, and colour in a way that I had hardly dared 

 to anticipate. The best way to mount them seems to be in a small 

 glass tube to contain the insect and solution. 



There are two well marked forms of case which may be roughly 

 described as the Fusiform and the Cylindrical. Mr. McEae told me 

 that from the former he always bred males, and from the latter always 

 females. I think this observation is correct as to the fusiform case, 

 from which I have never yet bred a female ; but I have occasionally 

 bred a male from a cylindrical ease, say about four altogether. 



The Grange, Waltham Cross : 

 July nth, 1900. 



[Formalin has latterly been employed for preserving the apterous 

 females of Psychidcs in several quarters, and with the best results. — 



Eds.] 



