NEW SERIES SUBSCRIPTION, $6.00VOL. 81, No. 2106 FRIDAY, MAY 10, 1935 SINGLE COPIES, .15

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PRATTIA MANUAL OF THE COMMONINVERTEBRATE ANIMALS

Revised Edition(Exclusive of Insects)

This revision has four definite objects: to bring up to date the nomen-clature of the species and, also, to revise the larger subdivisions of the animalkingdom; to introduce certain representative species which were not includedin the former edition; to increase representation from the fauna of the PacificCoast region, and to check all facts presented in the descriptions.

The manual gives a description of the common invertebrate animals bymeans of which their names and affinities can be determined. The analyticaltables and descriptions of species of each of the larger groups of animals arepreceded by a morphological description of the group together with someaccount of the habits and distribution of the animals. All technical termsappearing in the tables are explained. As a knowledge of the historical basis ofzoological names adds greatly to their significance, the author has given muchattention to this feature.

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BY HENRY SHERRING PRATT, PH.D.Professor of Biology, Haverford College

P. BLAKISTON'S SON & CO. Inc. Publishers1012 Walnut Street Philadelphia

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Geographic Distribution ofPocket Gophers (Genus Thomomys)

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A Comparison of the Distribu.tion of the Intestinal Protozoa

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THE ESSENTIALS OF PRACTICALMICROTECHNIQUEBy ALBERT E. GALIGHER

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THE JOURNAL OF NUTRITIONPublished monthly by The Wistar Institute

John R. Murlin, Managing Editor, University of Rochester

Vol. 9. Contents for June 1935 No. 6.ALFRED E. KOEHLER, IONE RAPP and ELSIE HILL. The nutritive value of lactose in man. One figure.ROBERT F. PITTS. The effect of protein and amino acid metabolism on the urea and xylose clearance. Three charts.K. E. MASON and J. M. WOLFE. Relation of castration to vitamin A-deficiency in the rat. Two figures.K. E. MASON and E. T. ELLISON. Changes in the vaginal epithelium of the rat after vitamin A-deficiency. Two plates.N. B. GUERRANT, R. A. RASMUSSEN and R. A. DUTCHER. The value of the chemical titration method in determining

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MAY 10, 1935 SCIENCE-ADVERTISEMENTS 7