INDEX TO AMERICAN BOTANICAL LITERATURE 409 
McBeth, I. G. Fixation of ammonia in soils. Jour. Agr. Research 9: 
141-155. f. I-3. 30 Ap 1917. 
Mendelson, W. Ophioglossum vulgatum—once more. Am _ Fern. 
Jour. 7: 63, 64. My 1917. 
Moore, C. W. Self-sterility. Jour. Heredity 8: 203-207. f. 2-4. 
25 Ap 1917. 
Murrill, W. A. (Agaricales.) Agaricaceae (pars), Agariceae (pars). 
N. Am. FI. 10: 77-144. 26 Ap 1917. 
ncludes d i f 100 new species in Claudopus (1), Eccilia (9), Lepioniella 
(13), Nolanea (11), " Pleatcake (3), Entoloma (33), Pluteus (28) and Volvariopsis (2). 
Patterson, F. W., & Charles, V.K. Some common edible mushrooms. 
U. S. Dept. Agr. Farm. Bull. 796: 1-24. f. 1-22. Mr 1917. 
Pease, A.S. Is Aster tardiflorusa hybrid? Rhodora 19: 88-90. 1 My 
1917. 
Pickett, F. L. The length of Erythronium stamens. Torreya 17: 
58—6o. f. r. 10 My 1917. 
Piper, C. V. The cowhage and related species. Proc. Biol. Soc. 
Washington 30: 51-62. 31 Mr 1917. 
Includes Stizolobium microspermum, S. venulosum and S. forbesii, spp. nov. 
[Popenoe, P.] Flower buds and leaf buds. Jour. Heredity 8: 236-239. 
7. 20+7 3 26 Ap ¥Or7. 
[Popenoe, P.] The hairs of nettles. Jour. Heredity 8: 240. f. 14. 
26 Ap 1917. 
Rhoads, A. S. The black zones formed by wood-destroying fungi. 
N. Y. State Col. Forest. Tech. Publ. 8: 1-60. pl. 1-6. Mr 1917. 
Robertson, C. Flowers and insects—XX. Evolution of entomophi- 
lous flowers. Bot. Gaz. 63: 307-316. 16 Ap 1917. 
Rock, J. F. The ornamental trees of Hawaii. i-v+1-210. pl. I-79 
+ frontispiece. Honolulu. F 1917. 
Rose, J.N. Dudleya Brandegei. Addisonia 2:15. pl. 48. 31 Mr 1917. 
Rose, J. N. Werckleocereus glaber. Addisonia 2: 13. pl. 47. 31 Mr 
1917. 
Rosett, J. Observations on a new type of artificial osmotic cell. Plant 
World 20: 37-57. f. 7-3. .F 1917. 
Rusby, H. H. Dircaea magnifica. Addisonia 2: 7, 8. pl. 44. 31 Mr 
1917. 
. Scott, C. A. A practical method of preventing damping off of coni- 
ferous seedlings. Jour. Forestry 15: 192-196. pl. 1, 2. F 1917. 
