CONTENTS OF VOLUME LIII V 



No. 6. DECEMBER. 1927. 



FOLGER, HARRY THOMAS. The Relation />V/<v<v;/ the Re- 

 sponses by Arnceba to Mechanical Shock and to Sudden 

 Illumination 40^ 



HILL, SAMUEL E. Chromosome Numbers in the Genus 



Bursa 413 



HINRICHS, MARIE A. Ultraviolet Radiation and the fertili- 

 zation Reaction in Arbacia punctulata 416 



WHITING, ANNA R. Genetic Evidence for Diploid Males in 



Habrobracon 438 



HAYWOOD, CHARLOTTE. Carbon Dioxide as a Narcotic 



Agent, I 450 



KING, ROBERT L. Origin and Description of Bristle in Dro- 



sopliila mclanogaster 465 



CHILD, C. M. Experimental Localization of New Axes in 

 Corymorplia Without Obliteration of the Original Po- 

 larity 469 



