CONTENTS 
Page 
Astronomy.— Relation or Preferential Motion and of the Spectral- Class and 
Magnitude Velocity Progressions to Proper Motion . . By C. D. Perrine 491 
Botany. — Growth of Isolated Sporophytes of Anthoceros ..." 
By Douglas Houghton Campbell 494 
Anthropology. — The Mesa Verde Types of Pueblos ... By J. Walter Fewkes 497 
Physics. — A Determination of the Ratio of the Specific Heats of Hydrogen at 
18° AND -190°C. . . c By Margaret C. Shields 502 
Physics.— Note on the Coefficient of Total Radiation of a Uniformly Heated 
Enclosure ^ByW.W. Cohlentz 504 
Physics. — ^The Development of a Source for Standard Wavelengths and the 
Importance of their Fundamental Values 
By Charles E, St. John and Harold D. Babcock 505 
Biochemistry. — On the Presence of Albumoses in Extracts of the Posterior 
Lobe of the Hypophysis Cerebri ... By John J. Abel and M. C. Pincofs 507 
Pathology. — On the Role of the Thymus in the Production of Tetanv .... 
By Eduard Uhlenhuth 517* 
Zoology. — Evidence of Assortive Mating in a Nudibranch . .By W. J. Crazier 519 
Zoology. — Corai, Reefs of Tutuila, with Reference to the Murray- Agassiz Solu- 
tion Theory By Alfred Goldsborough Mayer 522 
National Research Council, Suggestions Relating to the New National Army 
by the Anthropology Committee of the National Research Council . . . 526 
, First Report of Committee on Botany 529 
, Meetings of the Executive Committee , . 530 
