50 



THE COMMA BUTTERFLY. 

 (Polygonia comma Harr.) 



GEOGRAPHICAL DISTRIBUTION. 



This butterfly, which is one of the commonest of our northeastern 

 forms, belongs distinctively to the Alleghanian fauna, extending south 

 into North Carolina and Tennessee and north into various parts of 

 Canada, especially toward the east. It is found occasionally in small 

 numbers as far west as Wisconsin, Iowa, and Nebraska, and has been 

 recorded from Texas. Wisconsin is too far from its normal range to 

 allow it to be abundant in the hop fields, but in New York it is perhaps 



more frequently found 

 — ^. than the species which 



we have just discussed, 

 and, in fact, it is proba- 

 bly more abundant in 

 this State than else- 

 where. In New Eng- 

 land Scudder says that 

 it is nowhere a very com- 

 mon insect, but in West 

 Virginia, owing proba- 

 bly to local causes, it 

 is very numerous. The 

 insect is distinctively 

 called by Scudder u the 

 hop merchant," but, as 

 we have already shown, 

 the name is applied in- 

 discriminately to the 

 chrysalis of interroga- 

 tionis as well. 



HABITS AND NATURAL HIS- 

 TORY. 



In the hop-growing re- 

 gions of New York the 

 insect is double brooded, 

 the butterflies hibernating and flying in the early spring, living on into 

 the latter part of May and even June. The first brood of caterpillars 

 lives, in the main, upon elm, and youug elm trees recently set out are 

 frequently injured by the loss of almost their entire foliage in the 

 spring. Where the roots have taken hold, they recuperate from this 

 defoliation and put out another crop of leaves, but the damage is some- 

 times fatal to trees which have just been transplanted. Aside from the 

 elm, this early brood may also feed upon nettle and false nettle. The 



Fig. 38.— Polygonia comma: a, egg chain; b, larva; c, chrysalis; 

 d, adult— all natural size except a which is greatly enlarged 

 (original). 



