Professor Bouvier is one of the well-known personalities in the scientific world of Paris. His tall, spare, distinguished form and his keen, intellectual face are seen at the ceremonies of the Institut, at the meetings of the Academie des Sciences, the Societe de Biologie and the Academie dJAgriculture; and at other times one will find him, in his long linen laboratory coat, working among his specimens in the old zoological workrooms at No. 55 Eue de Buffon, just across the street from the Jardin des Plantes. He is a very broad zoologist. An old student of the late Edmond Perrier, he really began his active career at the period when evolutionary doctrines were being ardently contested, and he has fought valiantly at the side of Perrier, Gaudry, and Giard. His life has been a very productive one, and he has published a long list of important papers devoted for the greater part to marine articulates and especially to the Crustacea. He has produced, moreover, a magnificent monograph on the Onychophora, those extraordinary animals whose zoological position was so long disputed, and his studies on evolutionary mutations with certain sea forms of the family Atyidce have been of the first importance. Moreover, his work on the remarkable sea animals known as the Pycno-gonidcE, which are related in a broad way to the spiders, has made him a world authority on this group.

Bouvier, a quarter of a century ago, was appointed to the chair of articulate animals at the Museum d'Histoire Naturelle and from his laboratory has come a constant stream of important papers. Although working constantly with arthropods and having supervision of the labors of a number of famous entomologists and charge of the great entomological collections of the museum, for many years he personally did little work with insects, but in 1900 he became interested in the habits of certain nest-building Hymenoptera, and in that year and the next published three papers of very great interest as bearing on questions of instinct and behavior. Since the war he has retired from his official post, but it is impossible for a true naturalist like Bouvier to interrupt his work, and, curiously enough, he has gone back to the insects and is engaged at present upon a monograph on the great Saturnian moths whose larvae are the most famous silk-spinners in the world. During the war he remained at his post, caring for the collections, except for a journey which he took quite to Toulouse in the South of France to carry a large series of the most precious specimens away from the dangers of bombardment. In the course of the war he lost two of his children, and the present volume was written during those trying times, in the effort, as he wrote me in sending me a presentation copy, "pour oublier les angoisses de patriote et de pere."

I find this book, as I expected from a personal acquaintance with Bouvier for more than twenty years, to be a broad summary of an interesting field in which much work has been done by many men of many nations, but which is as yet almost unexplored. It has interested me enormously, and I feel sure that it will have the same interest, not only for students of some one restricted field of biology, but also for all nature-lovers, especially those to whom the constant question "why?" occurs.

Dr. W. M. Wheeler of Harvard University, in his appreciative review of the French edition of this book (published in the journal "Science" for November 13, 1920), called attention to several articles which should be read to supplement the consideration of certain topics in the book. Referring, for example, to the egg-laying of Ceropales, he mentions the very interesting observations of Adlerz (Bik. K. Svensk. Vet. Akad. Hand., 1902) on the surreptitious oviposition of this parasite in the lung-books of the spiders that have been captured by the host pompilid. He also refers to the important experimental contributions of Brun (1914) to the subject of the orientation and homing of ants and other animals. Further, he quotes from Needham and Lloyd's "Life of Inland Waters" (1916) in reference to the extraordinary habits of one of the American pom-pilids, as follows:

There is a black wasp, Priocnemis flavicornis, occasionally seen on Fall Creek at the Cornell Biological Field Station, that combines flying with water transportation. Beavers swim with boughs for their dam, and water striders run across the surface carrying their booty, but here is a wasp that flies above the surface towing a load too heavy to be carried. The freight is the body of a huge black spider several times as large as the body of the wasp. It is captured by the wasp in a waterside hunting expedition, paralyzed by a sting adroitly placed, and is to be used for provisioning her nest. It could scarcely be dragged across the ground, clothed as that is with the dense vegetation of the waterside; but the placid stream is an open highway. Out on to the surface the wasp drags the huge limp black carcass of the spider and, mounting into the air with her engines going and her wings steadily buzzing, she sails away across the water, trailing the spider and leaving a wake that is a miniature of that of a passing steamer. She sails a direct and unerring course to the vicinity of her burrow in the bank and brings her cargo ashore at some nearby landing. She hauls it upon the bank and then runs to her hole to see that all is ready. Then she drags the spider up the bank and into her burrow, having saved much time and energy by making use of the open waterway.

Doctor Wheeler appends to this quotation the statement that "additional peculiarities of habit among the Pompilids have been described by other authors, notably by F. X. Williams in a recent work on wasps of the Philippines (Bulletin No. 14, Experiment Station of the Hawaiian Sugar Planters ' Association, 1919)."

Wheeler adds, "Most readers will be delighted with Bouvier's book as it stands, with its lucid diction, its lack of dogmatic assertion, its kindly and stimulating tone and its frank acknowledgment of our ignorance in regard to many matters of fundamental importance."

To some readers the early chapters of the book may seem, in comparison with the later ones, somewhat dull and possibly irrelevant, but they are a necessary part of an admirably elaborated discussion leading from the earliest reactions of living matter to the acquisition of instinct, and so to the consideration of the characteristics of that sort of psychism that insects possess.

L. 0. Howard Washington, D. C, October 1, 1921.