GRAPTA I. 
that is very perplexing to lepidopterists who have but a limited acquaintance 
with them. And it is so contrary to the nature of the protean C album, which 
branches into forms that imitate several of the American species (see notes on 
Comma and Satyrus, Yol. I.), and into 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 differences 
between the larvae 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 Interrogationis, Vol. I., I suggested that Comma and Dry as might 
also prove to be dimorphic forms of one species, but I doubted if the case would 
be found parallel with Interrogationis, in which the two forms seemed to be 
of equal value, either one producing both at all seasons. It seemed probable, 
that Comma and Dry as appeared in the early summer brood, and Comma only in 
the autumn, and this, because I had always met with Dryas in summer and not 
later, when Comma was exceedingly abundant, especially in West Virginia. The 
relationship was finally established in 1873, by Mr. Mead and myself, at Coal- 
burgh, and again by myself 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 30th 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 habit with Interrogationis. By 5th 
August, the larvae 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 larvae. 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 ol Comma, Yol. I. fig a. 
Only one of the lot was yellow-white, as shown on the Plate of Dryas, and even¬ 
tually this one produced a Dryas butterfly. On 30th August, the butterflies 
began to emerge, and all were Comma, excepting six, 2 4 which were Dryas. 
This last, therefore, has caterpillars of both the white and the black types, and 
appears in the autumnal brood, though perhaps not so numerously as Comma. 
On the 10th 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. 
