246 THE CANADIAN ENTOMOLOGIST. 



slender, thickest in middle and tapering slightly to head ; the head case 

 compressed on dorsal side, so that there is an even slope from top of 

 mesonotum to the end ; this last is rounded, and at either end of the curve 

 the ocellar prominence is set, also rounded, and not projecting so far as 

 the top of the curve ; all this part thickly beset with short bristles ; the 

 mesonotum round and scarcely elevated , color greenish-yellow, or 

 greenish-brown, according to the color of the larva, covered with a 

 whitish mealy dust ; on either side of dorsum, at base of head case, is a 

 small round black process, surmounted by a circle of short bristles. 

 Duration of this stage when the imago comes forth the same season, about 

 seven days. From laying of egg to imago about thirty days. 



This pretty species flies quite generally throughout the United States 

 to Paciiic, and Mexico ; also in the southern part of British America. 

 Abbot says it is to be found about gardens and fields, and among melon 

 blossoms. It is somewhat abundant in some years in my own garden, 

 and I have observed it often about melon and cucumber patches, alighting 

 on the leaves. Probably its fondness for gardens is because its larval food 

 plant, pig-weed (Ambrosia) abounds in such places. I know of no other 

 food plant, but Abbot gives horse-mint, Monarda punctata. Origanum, 

 Chenopodium, which he calls lamb's quarters, and another plant called 

 " careless," but which neither Wood nor Gray help to identify. The egg 

 is laid singly on the upper side of a leaf, sometimes near the edge, but 

 generally near to the mid-rib. It is of a peculiar shape, quite different 

 from that of any species of Nisoniades which I have seen, and reminds 

 one of a confectioner's cake-mould, or of an inverted basket made of fine 

 willow twigs. The color, too, is peculiar, as compared with other Hes- 

 perian eggs, which are usually white or yellow-white when laid, being red- 

 brown, and looking on the leaf like a speck of dust. I have often found 

 several eggs on a stunted plant not more than two or three inches high 

 growing on the gravel walk. 



The young larva goes to edge of its leaf, cuts in about one tenth inch, 

 and folds over a corner so separated, binding it down by two or three 

 threads. Here it Hes concealed till the first moult has passed, and feeds 

 on the fleshy part of the leaf within the fold. After first moult the larva 

 draws the leaf together by the edges, and from second moult on the hiding 

 place is readily distinguished by the oval swelling of the leaf. When 

 about to moult the case is thickly lined with silk, and closed at every 

 point. The larvae come outside to feed and return to their cases, and 



