The total number of species of insects so far described from Florissant is about seven hundred, but several hundreds have been found, belonging to groups not yet worked up. The list, as it stands, contains only a single ant, but, as a matter of fact, ants are much more abundant than any other insects, at least in individuals. Those obtained by Scudder, and also the materials secured by the recent expeditions, are all in the hands of Dr. W. M. Wheeler, of the American Museum of Natural History. His account of them will be of extraordinary interest, based as it will be on the examination of thousands of specimens by a naturalist fully competent to make them contribute, not