44 THE CANADIAN ENTOMOLOGIST. 



east of Moline. These specimens are, if possible, fresher than those taken 

 July twenty-third. This species would, therefore, seem to be three 

 brooded in this latitude. There are also certain marked differences in 

 coloration, which may or may not be distinguishing characteristics of 

 seasonal varieties. The spring form, as it is represented by the single 

 specimen referred to, is distinguished by the absence of any indication of 

 the sub-marginal row of spots or points on the unders'ide of the wings or 

 any trace of orange, except the two spots on the upper surface of the hind 

 wings ; the rose pink ray extending outwards from the body on the hind 

 wings is present. The summer form, as it is represented by the six in- 

 dividuals in my collection, is marked as follows : — The sub-marginal row 

 of spots on the under surface of the wings are none of them pink ; those 

 in the interspaces of the first and second, and second and third ediman 

 veinlets, being black, the others brown ; the pink stripe on the under side 

 of the hind wings is entirely wanting, and there is on the upper surface of 

 the hind wings a sub-marginal area of orange, bright or faint, which some- 

 times extends froai) the marginal black band nearly to the orange discal 

 spot. There is also in all of these specimens a clearly defined oblong 

 raised patch of scales of peculiar form extending along the upper side of 

 the sub-costal vein of the hind wing, from the costal vein to the branching 

 of the first sub-costal veinlet. These scales seem to stand on end, and 

 although I have not satisfied myself of the fact, I think it is probably that 

 these scale-like bodies, are excrescences on the true scales. This patch 

 of scales seems to be confined to the males. It varies in colour from 

 yellow to reddish-orange. When it is yellow it is concolorous with the 

 adjacent surface, and not conspicuous, although the raised margin of the 

 outer edge is always very distinct on a closer examination. In the single 

 specimen of mine in which this area is reddish-orange, it is scarcely less 

 conspicuous than the " dog's head " when the anterior wings are pulled 

 forward far enough to expose it. Since it is present in all the males and 

 absent in all the females I have collected, I take for granted it is a sexual 

 mark. If this character has been described before, I have no knowledge of 

 the description, though it seems strange that it should have been overlooked. 

 Its presence would support Mr. Strecker and others in removing the species 

 from Colias. In the fall form, as represented by the three speci- 

 mens taken September sixteenth, the brown spots on the under sides of 

 the wings are replaced by pink ; the two black spots between the first and 

 second, and second and third median veinlets, remaining unchanged ; the 



