236 THE CANADIAN ENTOMOLOGIST. 



a variable extent, so that the new form is made permanent sooner in one 

 species than in another. From this there must follow a variability of the 

 generations concerned, that is, single individuals of the summer genera- 

 tion must differ more widely in markings and coloring than is the case 

 with those of the winter generation. The facts agree with this as regards 

 levana, the winter form being much more constant than the summer, and 

 in this (prorsa) it is hard to find two individuals exactly alike. 



So far I follow the paper. After reading it I wrote' Dr. Weismann as 

 to the peculiarity noticed by me that while out of doors, in the early 

 spring, Walshii was abundant, and for some weeks the only form of the 

 species to be met, I had scarcely ever been able to obtain it by breed- 

 ing, all the over-wintering chrysalids, with one or two exceptions, no 

 matter from which generation, producing telamonides. In the Supple- 

 mentary Notes to Butterflies of N. A., I had given the results of ninety- 

 two over-wintering chrysalids from eggs of many broods of the three 

 forms bred in 187 1, and not one Walshii appeared, while that same 

 spring, 1872, between the nth and 29th of April, Mr. Mead, at Coal- 

 burgh, had taken sixty-three specimens of Walshii, and had taken or seen 

 but one telamonides. To this Dr. Weismann replies : "The case of 

 Walshii and telamonides is indeed very singular and not easy to explain. 

 Nevertheless, I should believe that the ordinary warmth of the room in 

 winter is the cause which prevents the chrysalids acquiring the perfect 

 winter form Walshii. The case of ajax is more complicated than the 

 other cases of seasonal-dimorphism. It seems now to me possible that 

 not the form Walshii is the primary, but telamonides. It seems tela7n- 

 onides results from all generations. This primary form could have been 

 changed by summer heat into marcellits, by winter cold into Walshii. But 

 this would pre-suppose that telamonides has originated in the south and 

 there resided at the time of the great glaciers." 



Following the suggestions of Dr. Weismann, I have made experiments 

 the past season on the chrysalids of ajax, having bred from eggs laid by 

 var. telamonides the last of May many larvae, from which resulted between 

 22nd and 26th June, 122 chrysalids. These as fast as formed were 

 placed on ice in the refrigerator, in small tin boxes, and when all were 

 formed were transferred to a cylindrical tin box, four inches in diameter 

 and six high, and packed away in layers between thin partings of fine 

 shavings. (I used shavings because no better substance was at hand, 

 having found cotton liable to mould when exposed to dampness.) The 

 box was set in a small wooden box, and this was put directly on the ice 



