506 INDEX TO AMERICAN BOTANICAL LITERATURE 
Goodspeed, T. H. Modified safety-razor blade holder for temperature 
control. Bot. Gaz. 66: 176,177. f. r. 15 Au 1918. 
Graham, M. Centrosomes in fertilization stages of Preissia quadrata 
(Scop.) Nees. Ann. Bot. 32: 415-420. pl. ro. Jl 1918. 
Harper, R. M. A new seasonal precipitation factor of interest to 
geographers and agriculturists. Science II. 48: 208-211. 30 Au 
1918. : 
Harris, J. A. Secondary parasitism fin Phoradendron. Bot. Gaz. 66: 
275,°276. 16S 1918. 
Harshberger, J. W. Ecological society of America. The preservation 
of our native plants. Torreya 18: 162-165. 7S 1918. 
Hasselbring, H. Effect of different oxygen pressures on the carbo- 
hydrate metabolism of the sweet potato. Jour. Agr. Research 14% 
273-284. 12 Au 1918. 
Henderson, M. P. The black-leg disease of cabbage caused by Phoma 
lingam (Tode) Desmaz. Phytopathology 8: 379-431. f. 1-10. Au 
IQIS,.° ; 
Hibbard, R. P. Physiological balance in the soil solution. 
_ Agr. Exp. Sta. Tech. Bull. 40: 1-44. f. 1-8. S$ 1917. 
Holm, T. Joan Baptista Porta. Am. Nat. 52: 455-461. S 1918. 
Michigan 
Hotson, J. W. Sphagnum as a surgical dressing. Science II. 48: 
203-208. 30 Au 1918, 
Johnston, I. M. A few notes on the botany of southern California, 
Bull. So. Calif. Acad. Sci. 17: 64-66. Jl 1918. 
Johnston, I. M. Some undescribed plants from southern California. 
Bull. So. Calif. Acad. Sci. uf 63, 64. Jl 1918 
Lupinus elatus sp. nov. is describe 
Jones, D.F. The effect of REP and crossbreeding upon develop=- 
ment. Proc. Nat. Acad. Sci. 4: 246-250. 7% 2. Au rors. 
Keeler, H. L. The wayside flowers of summer. i-xiii+1-—288. New 
York. 1917. [Illust.] : 
Koessler, J. H. Studies on pollen and pollen disease.—I. 
ical composition of ragweed pollen. 
S 1918. 
Lipman, C. B., & Waynick, D. D. A bacteriological survey of the soil 
of Loggerhead Key, Tortugas, Florida. Proc. Nat. Acad, Sc: 4: 
232-234. Au 1918. 
Livingston, B. E., & Tottingham, W. E. A new three-salt nutrient 
solution for plant cultures. Am. Jour. Bot. 5: 337-346. 3 Au1918. 
The chem- 
Jour. Biol. Chem. 35: 415-424. 
