SILK-PEODUCING AND OTHER EXOTIC BOMBYCES. 24U 



common, and are the most difficult to bring to perfection in 

 confinement, as the.y will not eat in that situation ; and even if 

 they change into a chrysalis, they die afterwards." 



Before I finish with C. imj^ieriaUs, I must mention a peculiar 

 fact. During the first stage, and I think also during the second, 

 several larvae disappeared without leaving any traces. I also saw 

 two smaller larvse held tight by the hind claspers of two larger 

 ones. The larvse thus held and pressed were perfectly dead when 

 I observed them, and I removed them. My impression then was 

 that these larvae were carnivorous, not from this last fact alone, 

 as I had previously observed it with larvae of Catocalce when they 

 are too crowded, but from the fact that some had disappeared 

 entirel}' from the glass under which they were confined. I began 

 to reduce their numbers, and put six only under each glass, so as 

 to be able to watch them better. AVhether I had made a mistake 

 or not, previously to this, I do not exactl}' know ; but from this 

 moment the larvte behaved in a most exemplary manner, especially 

 when they became larger. They crawled over each other's backs 

 without showing the least sign of spite or animosit3% even when 

 they were in sleep, in which case larvae are generally very 

 sensitive and irritable ; all were of a most pacific nature. It is 

 therefore with the greatest pleasure that, for want of sufficient 

 evidence, I withdraw this serious charge of cannibalism which I 

 first intended to bring against them. 



Before I conclude this hastily-written article, I shall say a 

 few words on the difficulty of obtaining fertile eggs of Lepidoptera, 

 especially exotic species. I succeeded, as I had done before, in 

 obtaining fertile eggs of Deilephila eljpenor and D. eiqjhorbia, but 

 I had a large quantity of pupae of these two species. With the 

 American species of Sphingidae, such as Sphinx quinquemaculata, 

 Ceratomia quadricornis, and Daremma undulosa, it was a complete 

 failure, although I sacrificed all the moths, excepting a few. It 

 was the same with the European species, Smerinthus qiiercus. 

 These failures are due to the number of pupae being insufficient, 

 and also to other causes. The following statements on silk- 

 producing Bombyces will give an idea of some of the difficulties 

 found in the way when trying to reproduce exotic species in 

 captivity, and the losses incurred with these experiments : — 



Attacus Roylei. — Sixty cocoons. Moths emerged from March 

 5th to June 25th. One pairing, which I forgot to mention, took 



2 k 



