GRAPTA I. 



that is very jjerplexing to lepidopterists who have but a hmited acquamtance 

 with them. And it is so contrary to the nature of the protean G album, which 

 branches into forms that imitate several of tlie American species (see notes on 

 Comma and Satyrus, Vol. I.), and mto some that so far as known are not repre- 

 sented here, that it seems scarcely credible to those who are familiar with that 

 one species only. Fortunately the preparatory stages of most of the North 

 American species allied to C album, are known and described, and the diflerences 

 between the larvaj and chrysalids, sufficiently prove the distinctness of each such 

 species, from the others and from C album. 



It is a peculiarity of this genus that so many of the species are dimorphic. In 

 notes upon Interrogatlonis, Vol. I., I suggested that Comma and Dri/as might 

 also prove to be dimorphic forms of one species, but I doubted if the case would 

 be found parallel with Interrogatlonis, in which the two forms seemed to be 

 of equal value, either one producing both at all seasons. It seemed probable, 

 that Comma and Drt/as appeared in the early summer brood, and Conuna only in 

 the autunni, and this, because I had always met with Dryas- in sunimer and not 

 later, when Comma was exceedingly ahundant, especially in West Virginia. The 

 relationship was finally estaljlished in 1873, by Mr. Mead and myself, at Coal- 

 burgh, and again hy m^yself in 1874, and proves that the dimorphism has no sea- 

 sonal peculiarity. In the first instance, we obtained eggs of Dryas, by inclosing 

 two females in a muslin bag on a branch of hop-vine, of course, after examining 

 carefully to see that no eggs had been already laid thereon. This was 30tli July. 

 In a few hours there were many eggs deposited on the leaves and on the muslin, 

 and often in columns of four or five, as is the haljit with Inlerrogationis. By 5th 

 August, the larviv were hatched, and we carried them through their successive 

 moults with little loss, so that by 21st August, when the first changes to chrysalis 

 commenced, there were more than sixty mature larva?. There was not much va- 

 riation in their appearance, most of them being of a black ground, with more or 

 less yellow in short lines, and as represented on Plate of Comma, Yo\. 1. fig a. 

 Only one 'of the lot was yellow-white, as shown on the Plate of Dryus, and even- 

 tually this one produced a Dryas butterfiy. On oOth August, the ))utterflies 

 began to emei'ge, and all were Comma, excepting six, 2^,4*, which were Dryaa. 

 This last, therefore, has caterpillars of Ijoth tlie white and the black types, and 

 appears in the autumnal brood, though perhaps not so numerously as Comma. 



On the lOtli May, 1874, I took a female Comma, true to its type, the upper 

 side of hind-wings being red, and the under side of both wings plain brown, and 

 inclosed in same way as before related, after examining the branch to which I 

 fastened it. Within the next two days eggs were laid abundantly, and in due 

 time I counted thirty-nine caterpillars. 



