This book is a broad presentation of the field of freshwater biology, primarily in its scientific aspects, also in its relation to commercial, civic, aesthetic and public health interests of man. There is no book in the English language covering the field. Copiously illustrated with photographs from Nature. 438 pages; 244 figures. Price $3.00.
GAGE—Optic Projection
By SIMON HENRY GAGE, Professor Emeritus of Histology and Embryology in Cornell University, and Henry Phelps Gage, Ph. D.
This work of over 700 pages and with over 400 figures is of especial interest to workers in all fields of Biology in that it deals especially with the use of the Projection Microscope for demonstrations and for drawing. It also gives the fundamental principles of all the forms of projection. A 16-page circular will be sent on request. Postpaid, $3.00.
RILEY—Handbook of Medical Entomology
By WM. A. RILEY, Ph. D., Professor of Insect Morphology and Parasitology in Cornell University and O. A. JOHANNSEN, Ph. D., Professor of Biology in Cornell University.
A concise account of poisonous, and disease-carrying insects and their allies, including descriptions and illustrations of the principal species, with keys for their determination, and method of control. Bound Library Buckram, medium 8vo. Nearly 375 pages. Price $2.00 net.
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