262 



SCIENCE 



[Vol. LVI, No. 1444 



Further studies on the germination of trees 

 and shrubs: L. H. Pammel and Miss Chaklotte 

 il. King. 



The effect of weeds upon crop production: 

 A. L. Bakke and L. H. Pammel. 



Notes on species of Ehamnus of southwestern 

 United States and California and the occurrence 

 of Fuccinia coronata: L. H. Pammel. 



Structure and function of the stigma in rela- 

 tion to the germinative requirements of the 

 pollen in the Eastei- lily: J. N. Maktin, Fred C. 

 Werkenthin and Miss Elizabeth Httdson. 



The structure and development of the seed coat 

 and cause of delayed germination in Mellilotus 

 alba: J. N. Martin. 



The genus Cucurbita — Its origin, description 

 and Tcey to the species: Fred C. Werkenthin. 



The relation of the mosaic diseases of wild cat- 

 nip and cultivated cucumbers: J. H. Muncie. 



Studies of insect transmission and cross-inocu- 

 lation of mosaic on the Solanacece, Cucurbitacece 

 and Leguminacece : O. H. Elmer. 



Nodal infection of corn by diplodia: L. W. 



DUERELL. 



Effect of hardness of water on the fungicidal 

 value of mercuric chloride solutions: J. C. Gil- 

 man. 



A manual of ferns and "fern allies" of Grin- 

 nell and vicinity: Henry S. Conard. 



A manual of gymnosperms (evergreens) of 

 Iowa: Henry S. Conard. 



Parry's Catalog of Iowa Plants of 1848: Miss 

 WiNNiFRED Ellsworth. 



chemistry 



IOWA and AMES sections, AMERICAN CHEMICAL 

 SOCIETY 



A Study of dolomites from the Austrian Tyrol: 

 Nicholas Knight. 



The role of organic chemistry in plant and 

 animal therapy: Henry Oilman. 



A new method for the introduction of an ethyl 

 group: Rachel Hoyle, John B. Schxtmaker and 

 Henry Oilman. 



A rapid and inexpensive electrolytic determina- 

 tion of copper without the use of platinum 

 cathode: Stephen Popopp and T. C. Tucker. 



Inexpensive apparatus for use in large classes 

 of quantitative analysis: Stephen Popopp. 



The electrometric titration of tin. Critical 

 study of the standardization of solutions for use 

 in titration of tin: Stephen Popopp and F. L. 

 Chambers. 



The color of soils as an indication of plant 

 food content and fertility: P. E. Brown. 



A chemical classification of the activities of 

 soil micro-organisms : Paul Emerson. 



Water purification in Iowa: Jack J. Hin- 

 MAN, Jr. 



The electrometric determination of sulfurous 

 acid with permanganate: W. S. Hendrixson and 

 L. M. Verbeck. 



The electrometric standardisation of titanium 

 solutions: W. S. Hendrixson and L. M. Verbeck. 



The electrometric titration of organic acids: 

 J. H. Buchanan and C. J. Meister. 



The effect of the introduction of steam into 

 stop end retorts in the manufacture of coal gas: 

 George W. Burke. 



A note on lantern slide making : E. W. Bock- 

 wood. 



The relation of high school chemistry to college 

 chemistry: Edward Bartow. 



Studies on Yeast IV. On the presence of the 

 antineuritic and the growth promoting vitamines 

 in yeast grown in a synthetic medium: V. E. 

 Nelson, E. I. Ftjlmer and V. G. Heller. 



Studies on Yeast V. Is bios a single substance? 

 E. I. FuLMER and V. E. Nelson. 



A solubility survey — (1) An apparatus for the 

 determination of solubility up to the periodic sys- 

 tem : P. A. Bond. (S) A cross section of the 

 periodic system — solubilities in sulfur dioxide: 

 M, C. Waddell with P. A. Bond. 



Diacyl derivatives of ortho aminonaphthols : 

 L. Charles Radpord and K. C. Armstrong. 



The cost of softening water with various soaps: 

 O. E. Sweeney and Robert JVIcKinney. 



The possibilities of the commercial utilisation 

 of corn cobs: 0. R. Sweeney and H. V. Wright. 



Alhyl sulfates — (1) Studies on tjie equilibrium 

 between alcohols and sulfuric acid, and the sul- 

 fates and water: Harry F. Lewis. (S) The rela- 

 tive hydrolysis of the sulfates by water and acids: 

 H. F. Lewis and O'Neal Mason. (3) The in- 

 fluence of molecular weights on the hydrolysis: 

 H. F. Lewis and Arthur Damerow. 



Further data on the vitamin "A" content of 

 white and yellow corn: A. R. Lamb. 



The colorimetrio determination of hardness in 

 water: H. F. Lewis and Arthur Damerow. 



Recent attempts to disintegrate the atom: 

 Gerald L. Wendt and Clarence E. Irion. 



The decomposition of potassium chlorate. I. 

 Spontaneous decomposition temperatures. II. The 

 effect of pressure on decomposition: F. E. Brown, 

 J. Austin Burrows and H. M. McLaughlin. 



James H. Lees, 



Secretary 



