CONTENTS 



No. 1. JULY 



J . William Btjchaxan. The control of head formation in Planaria by means 



of anesthetics. Three figures 1 



J. ^1. D. Olmsted. The role of the nervous system in the regeneration of 



polyclad Turbellaria. Nine figures 49 



J. M. D. Olmstkd. The role of the nervous system in the locomotion of 

 certain marine polyclads 57 



Leoxell C. Strong. A genetic analysis of the factors underlying suscepti- 

 bility to transplantable tumors. Thirty-three figures 67 



No. 2. AUGUST 



Ruth L. Phillips. The growth of Paramecium in infusions of known bac- 

 terial content. One figure 135 



Carl G. Hartmax axd William F. Hamilton. A case of true hermaphrodit- 

 ism in the fowl, with remarks upon secondary sex characters. Two 

 plates (ten figures) 185 



G. H. Parker. The leaping of the stromb (Strombus gigas Linn.). Two 

 figures 205 



No. 3. OCTOBER 



Edgardo Baldi. Studi sulla fisiologia del sistema nervoso negli insetti. 

 II. Ricerche sui movimenti di maneggio provocati nei coleotteri. Quar- 

 anta figure -11 



F. B. StTMNER AND H. H. CoLLiNS. Further studies of color mutations in 



mice of the genus Peromyscus. Two plates (nine figures) 289 



G. H. Parker. The crawling of young loggerhead turtles toward the sea. . 323 

 William ^I. Goldsmith. The process of ingestion in the ciliate, frontonia. 



Three plates (twenty-five figures) 333 



DoxNELL Brooks Young. A contribution to the morphology and physi- 

 ology of the genus Uronychia. Three text figures and three plates 

 (twenty-eight figures) 353 



111 



I n^^f 



