THE VICTORIAN NATURALIST. 



83 



more densely hairy than the earlier ones. In about another 

 week, or five weeks' time from the date of hatching, the larvae 

 commenced making their cocoons. The first perfect specimen 

 emerged on 9th December, and was followed by the greater 

 part of the brood between that date and the 15th. All of 

 these specimens, about fifty in number, were similar to the 



parent — light forms 

 of obliqua, with just 

 ordinary variation. 

 Some pupae, however, 

 still remained, and 

 from these I was sur- 

 prised to breed, on 

 the 19th April, a very 

 dark specimen, which, 

 had it been captured 

 in the open, I should 

 have thought to be 

 fulvohirta. On the 

 26th April another 

 very dark specimen 

 appeared, and then 

 two ordinary forms on 

 the 3rd and 17th of 

 May ; finally I bred a 

 Without discussing this instance 



Figures of ordinary forms of S. obliqita 



very dark form on 3rd August 

 of irregular emergence, 

 though it is a subject 

 of much importance, 

 as illustrating the man- 

 ner in which a species 

 may be perpetuated 

 through unfavourable 

 seasons, I will proceed 

 to the consideration Fi e ure of dark form of s - ohU 'l" a - 



of the facts mentioned, which at first glance seem to confirm the 

 theory that the two species, obliqua send fulvohirta, are identical, in- 

 asmuch that ova deposited by undoubted obliqua produced about 

 8 per cent, of forms not to be distinguished from fulvohirta. 

 Having arrived thus far, I was anxious to secure ova of undoubted 

 fulvohirta, in order to ascertain whether they would produce a 

 corresponding percentage of light forms. Up to the present I 

 have failed to obtain ova, but I secured larva? fairly abundantly in 

 the ranges near Bayswater during November, and the larvae pro- 

 duced fulvohirta without exception, thus apparently proving that 

 the species is distinct, and upsetting the deductions made from the 

 previous experiment. I am, however, inclined to doubt whether 



