CONTENTS 
Pag* 
Astronomy. — ^Photographic Determination of Stellar Parallaxes with the 60- 
inch Reflector ....... By Adriaan van Maanen 187 
Chemistry.— On Chondrosamine . . By P. A. Levene and P. B. La Porgs 190 
Chemistry.— The Freezing-Point-Solubility Law for Ideal Solutions 
By Edward W. Washburn and John W, Read 191 
Chemistry.— Mercury Derivatives of Aromatic Amines. I. Structure of 
Primary and Secondary ^Amino-Phenylmercuric Compounds 
By Walter A, Jacobs and Michael Heidelberger 195 
Chemistry. — ^Molecular Rearrangements of Triphenylmethane Derivatives. 
I. General Discussion By Julius Stieglitz 196 
Chemistry. — ^Molecular Rearrangements of Triphenylmethane Derivatives. 
II. Experimental Part . . . By Julius Stieglitz and Collaborators 202 
Zoology. — ^Ecology of the Murray Island Coral Reef 
By Alfred Goldsborough Mayer 211 
Zoology. — Changes in Shade, Color and Pattern in Fishes and their Bearing 
ON Certain Problems of Behavior and Adaptation, . By S. 0. Mast 214 
Zoology. — ^Some Experiments on Spermatogenesis in Vitro. By Richard Goldschmidt 220 
Genetics. — Growth and Variation in Maize 
By Raymond Pearl and Prank M, Surface 222 
Bacteriology.— On a New Group of Bactericidal Substances Obtained from 
Hexamethylenetetramine . By Walter A, Jacobs and Michael Heidelberger 226 
Physiology.— Chemical and Physiological Studies of a Man Fasting Thirty- 
one Days . . . . . . . . By Prancis G. Benedict 228 
Anthropology.— The Study OF Indian Music . . . By Alice C. Pletcher 231 
Anthropology.— Some Recent Anthropological Explorations . 
, ; By Ales HrdlicH 235 
Mathematics. — ^The Second Derivatives of the Extremal Integral for a 
General Class of Problems of the Calculus of Variations 
By Arnold Dresden 238 
Mathematics. — Groups Possessing at Least One Set of Independent Genera- 
TORS^^MPQSED OF AS MaNY OPERATORS AS THERE ARE PrTMF. FaCTORS IN THE 
Order of the Group By G. A. Miller 241 
Mathematics.— Point Sets and Allied Cremona Groups . By Arthur B. Coble 245 
Mathematics.— The Straight Lines on Modular Cubic Surfaces 
By L. E. Dickson 248 
Anthropology.— The Diffusion of Horse Culture Among the North American 
Indians. .......... 5y Clark Wissler 254 
Paleontology.— Discovery of Algonkian Bacteria . By Charles D, Walcott 256 
A Correction By George P, Becker 257 
