1888.] 229 



INFOEMATION WANTED AS TO SELENIA ILLUNARIA, &c. 

 BY F. MEBBIFIELD, F.E.8. 



In connection witli some systematic experiments I am trying with 

 Selenia illunaria {bilunaria) and illustraria (tetralunaria),! should be 

 greatly obliged by information derived from personal knowledge, or 

 from trustworthy authorities, as to the distribution, time of appear- 

 ance, size, colour, and habits of these insects in different parts of 

 Europe, or of the British Isles, and should be grateful for fertile eggs 

 of typical specimens taken wild anywhere else than in the South of 

 England. There seems no doubt that both species are generally 

 double-brooded in the centre and south of Europe, and single-brooded 

 in the north ; and that where there is but one brood, it resembles in 

 size and markings the first or spring emergence in those places where 

 the insects are double-brooded. I will make any return in my power, 

 and can promise in the spring fertile eggs of both species from healthy 

 south of England examples. Guenee gives what appears rather 

 strange times of appearance for illunaria, which he describes as occur- 

 ring throughout Europe in March, April, and May, and then in 

 September and October. In the south of England, I believe, the second 

 brood appears in July, as stated in Mr. Stainton's Manual, but ex- 

 tending into August. There is another matter on which these two 

 authorities appear to differ. Mr. Stainton, speaking of illustraria in 

 its winged state, says that the summer or August brood is more 

 plentiful than the larger specimens of May. M. Guenee, speaking of 

 the caterpillars of the genus Selenia, writes as follows : " These 

 caterpillars live exclusively on trees, and have in general two genera- 

 tions : the first and most numerous, which is disclosed in autumn, 

 appears as a moth in the April or May following ; the second, 

 which is, so to speak, exceptional, though destined to ensure the 

 autumnal reproduction, gives in general but a small number of indi- 

 viduals. These circumstances, which, by the way, are common to 

 many other Lepidoptera, demand here particular attention, because 

 they touch on a question of variation among Lepidoptera which is not 

 yet entirely solved, and requires to be further investigated." There 

 is a further point on which I shall be glad of information, and it 

 relates to the third European species of the genus, viz., S. lunaria, 

 and that is as to the position of its wings at rest, whether it resembles 

 that of the wings of illunaria, which meet over the back like those of 

 a butterfly, or is more like the position of illustraria, which rests 

 with the wings recurved, but widely separated. May I suggest to 



