The first guide to the bees of the “Great Northwest” is presented in the hope that it will encourage the collection and study of these interesting insects in a region which is only now beginning to yiedl its treasures in this department of science.

The species are, in the main, arranged from generalized to specialized types; the groups follow one another, as in the recently proposed scheme of Mr. Charles Robertson, whose papers on the classificatios of bees have appeared, with few exceptions in this journal.