CONTENTS 



No. 1. APRIL 



J. Percy Batjmberger. A nutritional study of insects with special refer- 

 ence to micro-organisms and their substrata. Eighteen figures 1 



H. D. GooDALE AND Grace MacMullen. The bearing of ratios on theories 



of the inheritance of winter egg production 83 



No. 2. MAY 



William B. Kirkham. The fate of homozygous yellow mice. Two figures. 125 

 Carl R. Moore. On the physiological properties of the gonads as con- 

 trollers of somatic and psychical characteristics. I. The rat. Five 



figures 137 



Donald Walton Davis. A sexual multiplication and regeneration in 



Sagartia luciae Verrill. Ten plates (forty-two figures) 161 



Calvin B. Bridges. The genetics of purple eye color in Drosophila 265 



Edward C. Day. The physiology of the nervous system of the tunicate. 



I. The relation of the nerve ganglion to sensory responses. Five figures. 307 



No. 3, JULY 



Calvin B. Bridges. Specific modifiers of eosin eye color in Drosophila 

 melanogaster. Two diagrams 337 



C. H. Danforth. Evidence that germ-cells are subject to selection on the 

 basis of their genetic potentialities 385 



P. W. Whiting. Genetic studies on the Mediterranean flour-moth, Ephestia 

 ktihniella Zeller. One figure and two plates 413 



Wheeler P. Davey. Prolongation of life of Tribolium confusum appar- 

 ently due to small doses of x-rays. Four figures 447 



Carl R. Moore. On the physiological properties of the gonads as con- 

 trollers of somatic and psychical characteristics. II. Growth of 

 gonadectomized male and female rats. One figure 459 



David D. Whitney. The ineffectiveness of oxygen as a factor in causing 

 male production in Hydatina senta 469 



