I am indebted to my esteemed correspondent, Prof. C. H. Fernald, for a copy of his recent Synopsis of the Sphingidæ of New England. I have been greatly pleased with it, and trust that it will meet with that general distribution among the students of our beautiful science which it deserves. In the following lines I wish to present a few observations which the perusal of Prof. Fernald's book suggests.

Hemaris Tenuis, Grote.

Prof. Fernald remarks of this species: “The early stages and food plants are unknown.” Presuming that the statement of the learned Professor is warranted by an exhaustive search through the literature of the subject, I shall venture to supply from my own observation what strikes me as a surprising deficiency, since Hemaris Tenuis is one of our most abundant species in Western Pennsylvania.