644 
INDEX 
Soil chemistry (Lipman) 477, (Sharp), 563. 
Soils, nitrogen problem in arid (Lipman), 
477. 
Solids, effect of pressure on polymorphic 
transitions of (Bridgman), 513, 
Solar constant of radiation (Abbot, Fowle, 
and Aldrich), 331. 
Solubility, freezing-point law (Washburn 
and Read), 191. 
Solutions, aqueous, osmotic pressure of 
ions and molecules in (Bates), 363. 
Solutions, freezing-point-solubility law 
(Washburn and Read), 191. 
Solutions, liquid-ammonia (Franklin), 65. 
Solutions, potentials at junctions of (Mac- 
Innes), 526. 
Spectral colors, relative stimulating effi- 
ciency (Mast), 622. 
Spectra of planetary nebulae, line 4686 A 
(Wright), 266. 
Spectra, probable identities in wave-length 
in nebulae and stellar (Wright) 596. 
Spectra, Thiele's Thase' in (Uhler), 487. 
Spectra, tube-arc and spark (King), 371. 
Spectral class of double stars (Aitken), 530. 
Spectral classes of stars (Seares), 481. 
Spectra, classification of nebulae by their 
(Wright), 590. 
Spectrum, beyond Schumann region 
(Lyman), 368. 
Spectrum, flash without eclipse (Adams 
and Burwell), 127. 
Spectrum, lines in iron arc (St. John and 
Babcock), 131. 
Spectrum of iron arc (St. John and Bab- 
cock), 295. 
Sperm dilutions of Arbacia (Lillie), 156. 
Spermatogenesis, experiments on (Gold- 
schmidt), 220. 
Spermatozoa, dimorphism of (Zeleny and 
and Faust), 91. 
St. John, C. E. Critique of the Hypothe- 
sis of Anomalous Disperion in Certain 
Solar Phenomena, 21. 
St. John, C. E. and Babcock, H. D. On 
the Pole Effect in the Iron Arc, 295. 
. Variability of Spectrum Lines in 
the Iron Arc, 131. 
Stagner, B. a., see Stieglitz, J., 205. 
Stars, binary (Stebbins), 260. 
Stars, Cepheid variable (Shapley and Shap- 
ley), 452. 
Stars, of spectral types F, G, K, M (Kap- 
teyn and Adams), 14. 
Stars, radial velocities of (Adams), 417. 
Star colors, distribution in N. G. C. 1647 
and M 67 (Seares and Shapley), 483. 
Star colors, notation for (Seares), 481. 
Star streams (Kapteyn and Adams), 15. 
Stebbins, J. Some Problems in Stellar 
Photometry, 259. 
Sterility, self- (East), 95. 
Stellar evolution, Nova-Nebula- Wolf -Rayet 
(Adams and Pease), 391. 
Stellar evolution, role of density (Shapley), 
459. 
Stellar parallaxes (van Maanen), 187. 
Stellar photometry, problems in (Stebbins), 
259. 
Stewart, O. J., see Baxter, G. P., 77. 
Stieglitz, J. Molecular Rearrangements 
of Triphenylme thane Derivatives. I. 
General Discussion, 196, II. Experi- 
mental Part (with collaborators), 202. 
Stockard, C. R. An Experimental Analy- 
sis of the Origin and Relationship of 
Blood Corpuscles and the Lining Cells 
of Vessels, 556. 
Stocking, R. J. Variation and Inheri- 
tance in Abnormalities Occurring after 
Conjugation in Paramecium cauda- 
tum, 608. 
Stylonychia pustulata, heredity of fission 
rate (Middleton), 616. 
Sun, anomalous dispersion in (St. John), 
15. 
Sun, electricity in atmosphere of (Hale and 
Babcock), 123. 
Sun, flash spectrum (Adams and Burwell), 
127. 
Sun-spot vortices, direction of rotation 
(Hale), 382. 
Sun-spot vortices, illustrated by experi- 
ments (Hale and Luckey), 385. 
Surface, F. M., see Pearl, R., 222. 
Surfaces, isothermally conjugate curves on 
(Green), 516. 
Surfaces, transformations of (Eisenhart), 
62. 
Surfaces, transformations of curves on 
(Eisenhart), 290. 
Surface-tension, determination of (Richards 
and Coombs), 404; (Harkins andHum- 
phery), 585. 
Swezy, O., see Kofoid, C. A., 315. 
Symphalangism (Gushing), 621. 
Talbot, F. B., see Benedict, F. G., 600. 
Tashiro, S. On the Nature of the Nerve 
Impulse, 110. 
Temper, heredity of (Davenport), 37. 
Temperament, inheritance of (Davenport), 
456. 
Temperature, effect on aberration (Schles- 
inger), 13. 
Thorvaldson, T., see Baxter, G. P., 71. 
Transference experiments (Washburn and 
Millard), 142. 
Transformations of conjugate systems with 
equal invariants (Eisenhart), 290. 
Transformations of surfaces (Eisenhart), 
62. 
Trelease, W. Phoradendron, 30. 
Triad systems (White), 4. 
Tribal rites of Indians (Fletcher), 467. 
Tribal societies among the Plains Indians 
(Wissler), 401. 
Trichomonas, mitosis in (Kofoid and 
Swezy), 315. 
Triphenylmethane derivatives (Stieglitz), 
196. 
