DIVISION OF ENTOMOLOGY, 
Y/ashington, Y). C., -. May 5th, . i8g'^* . 
Prof, Sereno Watson, 
Botanical Garden, 
Cambridge, Mass, 
My dear Sir; 
I was much pleased to receive, this morning, your 
favor of the 30th ultimo, with enclosures, the more pleased be- 
cause I had read at the last meeting of the Washington Entomolog- 
ical Society an article on the determination of the food-plant of 
Garpocapsa saltitans . of which I send you a copy enclosed. Your 
specimens enable me now to speak with certainty of the species 
bred from the bi-cocoous form, which, by the way, is marked 
bilocular is in the herbari-um here, I presume it is the same as 
what you call bi-cap sularis , ¥ou will notice that I had already 
arrived at the conclusion that G, saltitans affects several species 
of the genus, if not different genera. In this connection I would 
like to ask you whether you are familiar with the meaning of 
Colliguaja, You will see, upon reading over my article, why I 
ask the question, I cannot find anyone here who can give me an 
explanation, as it seems to be a Mexican or native term and pro- 
bably has reference to some common attribute of the Euphorbiaceae , 
