72 INDEX TO AMERICAN BOTANICAL LITERATURE 
Tidestrom, I. Tsuga canadensis (L.) Carr. Rhodora 20: 185-188. 
11 N 1918. 
Tottingham, W. E. The sulfur requirement of the red clover plant. 
Jour. Biol. Chem. 36: 429-438. pl. rz. N 1918. 
Trelease, W. The ancient oaks of America. Brooklyn Bot. Gard. 
Mem. 1: 492-501. pl. 13-22. 6 Jl 1918 
Trowbridge, C. C., & Weil, M. The coefficient of expansion of living 
tree trunks. Science II. 48: 348-350. 4 O 1918. 
True, R. H. Joseph Young Bergen. Bot. Gaz. 66: 455-458. 15 N 
1918. [Portrait.] 
True, R. H., & Harvey, R.B. The absorption of calcium salts by squash 
seedlings. Brooklyn Bot. Gard. Mem. 1: 502-512. f. 1-3. 6 Jl 
1918. 
_ Vries, H. de. Kreuzungen von Oenothera Lamarckiana mut. velutina. 
Zeits. Induk. Abst. Vererbungslehre 19: 1-38. Mr 1918. 
Vries, H. de. Twin hybrids of Oenothera Hookeri T. and G. Genetics | 
3: 397-421. S 1918. 
Walker, R.S. The liberty-oil Bee Am. Forestry 24: 612-614. O 
1918. 
Weatherwax, P. ioonrend technique for corn pollination. Proc. 
Indiana Acad. Sci. 1917: 105-107. f. 1, 2. 1918. 
Weatherwax, P. Variation and varieties of Zea Mays. Proc. Indiana 
Acad. Sci. 1917: 99-103. 1918. 
Wellington, R. Raspberry breeding. Proc. Soc. Hort. Sci. 1912: 
155-159. Mr 1913. 
Wernham, H. F. Tropical American Rubiaceae—X. Jour. Bot. 55: 
336-341. 1917;—X. The genus Manettia. Jour. Bot. 56: (Suppl.) 
1-8. 918 
Includes description of six new species in Psychotria (2) and Palicourea (4). 
White, O. E. Inheritance studies on castor beans. Brooklyn Bot. 
- Gard. Mem. 1: 513-521. pl. 23-28. 6 Jl 1918. 
Wieland, G.R. A study of some American fossil Cycads. Part VIII. 
Notes on young floral structures. Am. Jour. Sci. 46: 645-650. f. I. 
N 1or18. 
Wilson, O. T. A storage fermentation of dasheens. Phytopathology 
8: 547-549. f. 1. O 1918. 
Wolfe, J. J. Alternation and parthenogenesis in Padina. Jour. 
Elisha Mitchell Sci. Soc. 34: 78-109. pl. r. S 1918. 
