THE CANADIAX ENTOMOLOGIST. 9" 



given by him ; but there are some structural points in Avhich it differs from 

 Bntalis, and Dr. Clemens' specific description is applicable to only a 

 small proportion of individuals out of the many that I have examined. 

 My specimens have been bred from larvae found mining the leaves of the 

 great hog weed (Ambrosia trifida) and ^•arious species of Aster (A. 

 ericoides and A. sagittifolius). It spins a small web on the under side of 

 the leaf from which it passes into the leaf, eating out the parenchyma in 

 small patches. It makes several mines before passing into the pupa 

 state. The mine is at first convoluted, narrow and filled with frass, but 

 soon becomes a clear transparent blotch somewhat like the mine of 

 Btdellia sommihuteUa in leaves of the morning glory {Ipoiiiea). It pupates 

 in a dense web which it spins around itself, and which is but slightly 

 attached to the surface of the leaf 



In the imago state the tongue is scaled at the base only, the wings are- 

 carried slightly deflexed in repose instead of being folded around the 

 body as in the true species of Butalis. The primaries have only three 

 instead of four veins beneath the apical one, and the head is rather less 

 obtuse and is scarcely at all retracted. I had at first inclined to erect for 

 it a new genus, and specimens in my cabinet were labelled Since 

 ambrosiaee//a, and have been distributed to some correspondents under 

 that name. The neuration of the wings is very similar to that of the 

 genus Aybia, but the palpi are very different. 



The imago is shining bronzy dark brown, with a purplish tinge. 

 Usually there is a whitish yellow spot on the fold of variable size, some- 

 times spreading to the dorsal margin, sometimes scarcely discernible, and 

 sometimes absent : there is always a distinct streak of the same hue at 

 the beginning of the dorsal cilia, and a white patch on the abdomen 

 beneath near the apex. Al. ex. ^4 inch. 



The larva is at first white with green contents ; then a small black 

 spot appears on each side of the first segment, and afterwards a series or 

 line of similar spots extends along the entire length of the larva and 

 ultimately they become purple. In the later larval stages a purple line 

 appears on each side of the median one. There is a small blackish spot 

 behind each eye. In the adult larva the 9th and loth segments become 

 purple on top and the purplish longitudinal lines above mentioned are 

 connected on the posterior margin of each segment by a transverse band 

 of the same hue. It has sixteen feet, the thoracic ones being piceous. It 

 may be found in all of its stages from June until the fall of the leaves. 



