The Quarterly Review of Biology 



MARCH - JUNE - SEPTEMBER - DECEMBER 

 RAYMOND PEARL, Editor 



Institute for Biological Research 

 The Johns Hopkins University 



ASSISTED BY 



R. W. Hegner Blanche F. Pooler John Rice Miner 



Contributing Editor Assistant Editor Assistant Editor 



The Johns Hopkins University 



Advisory Board 



ANATOMY Lewis H. Weed The Johns Hopkins University 



ANTHROPOLOGY A. L. Kroeber University of California 



BEHAVIOR AND COMPARA- 

 TIVE PSYCHOLOGY K. S. Lashley University of Minnesota 



BOTANY Irving W. Bailey Harvard University 



CYTOLOGY Edmund B. Wilson Columbia University ' 



ECOLOGY William Morton Wheeler Harvard University 



EMBRYOLOGY E. G. Conklin Princeton University 



EXPERIMENTAL MOR- 

 PHOLOGY Ross G. Harrison Yale University • 



GENERAL PHYSIOLOGY /Lawrence J. Henderson 



IG. H. Parker Harvard University \ 



GENETICS P^"* ^' Emerson Cornell University 



'IT. H. Morgan Columbia University 



GEOGRAPHICAL DISTRIBU- 

 TION AND TAXONOMY. . . . .Alex. G. Ruthven University of Michigan 



PALEONTOLOGY John C. Merriam Carnegie Institution 



ZOOLOGY Frank R. Lillie University of Chicago 



Interesting Papers to Appear in Early Numbers 



Animal Evolution. Austin H. Clark, Smithsonian Institution. 



Life Zones. E. W. Nelson, Bureau of Biological Survey, U. S. Department of Agriculture. 



Sub-Human Culture Beginnings. A. L. Kroeber, University of California. 



The Cytology on Glandular Secretions. R. H. Bowen, Columbia University. 



Facial Expression. Ernst Huber, Johns Hopkins University. 



The Metabolism op Insects. Mary H. Sayle, University of Wisconsin. 



The Problem of Senescence and Rejuvenescence in the Protozoa. L. L. Woodruff, 



Yale University. 

 The Chloroplast Pigments. Frank M. Schertz, Washington, D. C. 

 The Gene. Richard Goldschmidt, Kaiser Wilhelm Institut fur Biologic. 



Copyright 1928, The Williams & Wilkins Company. 



Entered as second-class matter January 27, 1926, at the post office at Baltimore, Maryland, under the Act of March 3, 1876. 



$5.00 a year ($5.50 outside Postal Union) $1.50 a copy. 



Made in United States of America 



