294 THK KNTOMOMXilS'r's llKCOKIt. 



mentions that various silkworm l)reotlers in Breslau anrl ]\Innieh gave 

 him similar information, and one of them, Herr Steiner of Breslau, 

 enabled him to carry out some experiments on an extensive scale. He 

 noticed " exactly the same well-known change of colour which took place 

 in the fertilised eggs soon after their deposition " in a large number of un- 

 fecundated eggs as had previous observers, but many stopped at various 

 stages, some only becoming reddish or violet, and very few unfertilised 

 eggs passing through the entire series of colour-change to slaty-grej-. 

 Siebold obtained no larvae from them, but in 1854, Herr Schmid of 

 Eichstadt sent him unfertilised eggs from which he got larva?. He tells 

 us that lie expected to ])reed onl}^ males, his mind having already been in- 

 fluenced in the matter by reading Lacordaire's account of Carlier's obser- 

 vation " that he obtained, without copulation, three generations of Lipariti 

 dispar, of which the last gave only males, which naturally brought the 

 experiment to an end." Siebold, however, reared both males and 

 females, which copulated freely, and appeared to have quite the ordinary 

 amount of vitality, whilst Dr. Kipp had previousl}^ recorded the rearing 

 of both males and females from some unfecundated eggs of Smerinthus 

 popnli. Schmid at the same time made some experiments which gave 

 a similar result. 



Err.\tum. — Page 246, line 22, for " octoderm " read ectoderm. 



SCIENTIFIC NOTES & OBSERVATIONS. 



Notes on the Life-historv of Melanippe rivata and M. sooiata. 

 — Writing of the specific distinctness of these two geometers, which 1 

 sujipose no one with any knowledge of them could now question, 

 Newman (p. 162), quotes Hellins as saying that " The difficulty of ob- 

 taining both species in the same stage, at the same time, no doubt i-en- 

 ders this comparison" (of the larv;e)" less perfect than it might )»e, could 

 they be placed side l)y side," kc, &c. This remark has always surprised 

 me, and shows either that Mr. Hellins did not take any great pains in 

 the matter, or else that M. rirnta occurs earlier, or lasts for a shorter 

 period, in some districts, than in tlie Isle of Wight. It is quite true that 

 the time of the appearance of rivata in the imago state is, roughly 

 speaking, intermediate between the two broods of sociata, but at San- 

 down, the two always overlap in the latter part of July and first few 

 days of August, for a period of from two to three weeks, according to 

 circumstances. Of course, for the purpose of a comparison of the larvae, 

 it matters not that rivata has been on the wing longer than sociata, 

 since I have always found that, however worn it is, it is good for a 

 few eggs at least, and I have sometimes obtained quite fresh specimens 

 after sociata was well out. By the way, I strongly suspect that 

 Newman's statement that rivata is " never double-brooded in a state of 

 nature," is not quite accurate ; it is, in captivity, a somewhat erratic 

 species, some broods keeping rigidly to the long pupal period, others 

 producing one or two precocious imagines in the autumn, while a friend 

 of mine had one small brood (from a June ? ) which reached the imago 

 state the same summer — I believe in only five or six weeks. I, unfortu- 

 nately, have only limited opportunities of collecting in June, but the 

 rivata which I l)reed emeroe from the extreme end of Mav to aliont 



