( Ixix ) 
described by me in 1891,* I noted what appeared to be un- 
doubted cases of seasonal dimorphism in species of Acreine, 
Lycenide and Pierine ; and again, in cataloguing Mr. F. C. 
Selous’s Manica butterflies in 1894,r I showed reason for 
recognising the prevalence of the same kind of variation, 
especially pointing out how in the case of Melanitis leda all 
the dated South African examples went to confirm De Nice- 
ville’s experience at Calcutta, and what strong similar ground 
existed for considering the much-discussed variation in the 
Nymphaline Hamanumida dedalus to be seasonal. 
An important contribution to the elucidation of the subject 
was made in 1894 by the late Capt. EK. Y. Watson in a paper 
entitled ‘‘ Notes on the Synonymy of some Species of Indian 
Pierine.” + 
According to this experienced entomologist’s observations 
some species—Terias hecabe, for instance—produce successive 
broods (from four in the cooler to ten or twelve in the 
warmer districts) throughout the year, and the last alone of 
the wet-season or dry-season broods respectively yields off- 
spring exhibiting the opposite seasonal form ; but it is at the 
same time pointed out that “in some cases the eggs laid by 
one female would produce more than one form, according to 
the state of the atmosphere shortly before the emergence of 
each individual, which is the period at which it would be 
chiefly affected.” The author calis attention to the fact that 
“in different parts of the Indian Region, the seasons vary to 
a certain extent, so that it cannot be laid down that speci- 
mens captured in any particular month will belong to any 
particular form”; he defines, however, roughly the limits of 
the rainy and dry seasons and states that “the very large 
majority of specimens obtained during those periods will be 
wet- and dry-season forms respectively.” Emphasis is laid 
on another important point, viz., that the seasonally dimor- 
phic species present numerous intermediate forms, and that 
these intermediate forms themselves vary according to the 
* Proc. Zool. Soc. Lond., 1891, pp. 59, 64, 85, 89, 96, 97, and 99. 
+ Op. cit., 1894, pp. 14, 22, 29, 37, 64, and 67. 
+ Journ. Bombay Nat. Hist. Soe., viii, p. 489 (1894). 
PROC. ENT. SOC. LOND. v., 1898. FE 
