146 THE CANADIAN ENTOMOLOGIST. 



made, I had thought Mandan of New England and eastern Canada might 

 be distinct not only from Palcemon of Europe, but also from Mandan of 

 the Bow Valley. That idea I can no longer entertain. The amount of 

 variation among my few instances of Palcemon proves to be greater than 

 I have hitherto considered it, and this fact lessons the probability that the 

 name Mandan covers two species. My reasoning is : — (i) The Euro- 

 pean Palcemon is so uniform in size and colour, and presents, its 

 variations in a manner so undemonstrative, that the true values of its 

 variations are easily recognized, and it is readily seen that the several 

 variational phases constitute but a single species. (2) Mandan, like 

 many other of our lepidoptera, is strongly influenced by the meteoro- 

 logical peculiarities of widely separated districts inhabited by it in North 

 America, and in certain extreme conditions displays its variational 

 capacity with a freedom, an exuberance, quite in contrast to the conserva- 

 tive variation of species in Europe. (3) As I find the variation in 

 Palcemon essentially as important as the more emergent and erratic 

 variation shown in certain environments by Mandan, and as Palcemon in 

 its various attitudes is inseparable from corresponding aspects of 

 Mandan and helps to render evident the unity of Mandates extreme 

 phases, I am therefore led to believe Mandan contains but one species, 

 although it has been so well supplied with synonyms and its extremes of 

 colour variation are so great. 



In the material at hand, together with the Mandan literature acces- 

 sible, I find no indication of more than one species, unless it be the 

 difference in food-plants — The Nepigon and Bow Valley sections eating 

 grasses, while Palcemon of Europe is said to feed on Plantago major. 

 This diversity does not greatly impress me, as the " unexpected " in that 

 line often happens. After discovering (Aug. 5, 1889) that Colias nastes 

 eats Willow, and having (in August, 1890) persuaded Grapta zephyrus 

 to accept a diet of rose, I am prepared for almost any specialty in food- 

 plants. Melitcea anicia feeds on two species of plants, or more ; so does 

 Lyccefia aquilo. 



From the insects compared I have the following information. The 

 Banff specimens agree with the Laggan series. The Nepigon $ is almost 

 a copy of one Finland S — if smaller, the difference is very slight ; it 

 differs above forewing in having the median yellow-brown spots shorter 

 (partly obliterate) ; on under side the Finland example is more suffused 

 with yellow and the spots under hind wing are less clear; in ev'ery 



