(Wii) 
telamonides, and the summer form known as marcellus appears 
in three similar generations—Mr. Edwards, by the applica- 
tion of ice for a period of two months, found that fifty pup 
reared from eggs laid by the second generation of the 
winter form (telamonides), which under natural conditions 
would nearly all have given the summer form marcellus, 
produced no fewer than twenty-two telamonides, one speci- 
men intermediate between telamonides and walshii, eight 
examples intermediate between telamonides and marcellus, 
but nearer to the former, eight intermediate between the 
same forms but nearer to the latter, and only eleven true 
marcellus. It should be observed, however, that there is a 
difference in the shape of the wings between the winter and 
summer forms of this Papilio, and that the strong innate 
tendency of the progeny of the winter form to assume 
the summer form was evidenced in the fact that all the 
butterflies from the refrigerated pupz which had the 
markings of telamonides or of walshit yet bore the shape 
of marcellus. 
The extreme variability of Phyciodes tharos renders it 
difficult to follow the details of Edwards’ experiments with 
the various broods from different districts, but it is clear 
that, as in the case of P. ajax, the application of cold in- 
duced the summer form to revert to the winter form (marcia). 
I do not gather that the converse experiment was tried with 
this butterfly ; but it was attempted to a certain extent with 
Papilio ajax, whose hibernating pupe were subjected to a 
moderate degree of heat during some months, for several 
years in succession, without any change being effected in the 
resulting winter form of the butterfly. The evidence in the 
case of Grapta interrogationis has a different bearing on the 
subject, seeing that this species does not hibernate as pupa 
but as imago, and that therefore there is not, strictly speak- 
ing, any “ winter” form; but it would appear that the first 
of the four broods in the year consists wholly of the form 
named wmbrosa and the fourth of the form named /fabriciz, 
while the intervening second and third broods are each com- 
posed of both forms. 
Only brief reference is made by Weismann to the experi- 
