CONTENTS 
Page 
Astronomy. — Some Problems in Stellar Photometry . By Jod Stehhins 259 
Geochemisiry. — ^The Composition or Brachiopod Shells 
By F. W. Clarke and W. C. Wheeler 262 
Astronomy. — On tHE Occurrence of the Line 4686A and the Related Series of 
Lines in the Spectra of the Planetary Nebulae . By W. H. Wright 266 
Physiology. — The Nature of Nerve Conduction in Cassiopea 
By Alfred Goldshorough Mayer 270 
Mathematics. — A New Canonical Form of the Elliptic Integral 
By Bessie I, Miller 274 
Chemistry, — ^The Structure of Complex Atoms and the Changes of Mass and 
Weight Involved in Their Formation 
By William D. Harkins and Ernest D, Wilson 276 
Genetics. — Huntington's Chorea in Relation to Heredity and Eugenics . 
By C. B. Davenport 283 
Zoology. — ^The Alcyonaria as a Factor in Reef Limestone Formation . 
By L. R. Gary 285 
Mathematics. — ^Transformations of Conjugate Systems With Equal Invari- 
ants By Luther PfaUer Eisenhart 290 
Physics. — On the Pole Effect in the Iron Arc 
By Charles E. St. John and Harold D. Babcock 295 
Genetics.—Inheritance in the Asexual Reproduction of Hydra Viridis . 
ByK. S, Lashley 298 
Mineralogy. — On the Monticellite-Like Mineral in Meteorites, and on 
Oldhamite as a Meteoric Constituent . . . By George P. Merrill 302 
Astronomy. — Absolute Scales of Photographic and Photovisual Magnitude 
By Frederick Seares 309 
Zoology. — Mitosis in Trichomonas . By Charles Atwood Kofoid and Olive Swezy 315 
Report of the Annual Meeting 322 
