530 INDEX TO AMERICAN BOTANICAL LITERATURE 
Murrill, W. A. Melanoleuca pulverulentipes Murrill, sp. nov. Myco- 
logia 9: 179. My 1917. 
Murrill, W. A. The rosy-spored Agarics. Mycologia 9: 179, 180. 
9 Je 1917. 
Nash, G. V. Catasetum viridiflavum. Addisonia 2: 25. pl. 5 3- 30 Je 
I9I7. 
Nash, G. V. Feijoa Sellowiana. Addisonia 2: 37. pl. 59. 30 Je 1917. 
O’Gara, P. J. Notes on the distribution of the bacterial disease of 
western wheat-grass. Phytopathology 7: 225, 226. 2 Je 1917. 
O’Gara, P. J. The occurrence of Colletotrichum solanicolum O’Gara 
on egg plant. Phytopathology 7: 226, 227. f. 1. 2 Je 1917. 
Orton, C.R. How trees grow. Proc. Fruit Growers Assoc. Adams Co. 
1913: 67-72. I914. 
Orton, C. R. Plant diseases with relation to forestry. Pennsylvania 
State Farmer 6: 122-126. 1913.  [Illust.] 
Orton, C.R. Report of the Department of Botany. Ann. Rep. Penn- 
sylyania State Col. Exp. Sta. 1912-1913: 147-151. 1914. 
Orton, C. R. Some important diseases of the farm and orchard with 
methods of control. Pennsylvania State Farmer 6: 122-126. 1913. 
[Illust.] 
Payson, E. B. The perennial scapose Drabas of North America. Am. 
Jour. Bot. 4: 253-267. 31 My 1917. 
Fourteen new species are described. 
Pease, A.S. Taraxacum ceratophorum in New England. Rhalee 19: 
411, 112. Je 1947. 
Pieper, E. J., Humphrey, C. J., & Acree,S.F. Synthetic culture media 
for wood-destroying fungi. Phytopathology 7: 214-220. 2 Je 1917. 
Pierce, R.G. Early discovery of white pine blister rust in the United 
States. Phytopathology 7: 224, 225. 2 Je 1917. 
Pipal, E. J. A list of plant diseases of economic importance in Indiana 
with bibliography. Proc. Indiana Acad. Sci. 1915: 379-413. 1916. 
Plummer, J. K. Some effects of oxygen and carbon dioxide on nitri- 
fication and ammonification in soils. Cornell Agr. a Sta. Bull. 
384: 305-330. f. 66-70. D 1916. 
Povah, A. H. W. A critical study of certain species of Mucor. Bull. 
Torrey Club 44: 241-259. 22 My 1917; 287-313. pl. 17-20. 13 
Je 1917. 
Six new species are described. 
Prentice, B. N. Some elementary notes on stem analysis of white oak. 
Proc. Indiana Acad. Sci. 1915: 153-160. 1916. [Illust.] 
Ramsey, G. B. A form of potato disease produced by Rhizoctonia. 
Jour. Agr. Research 9: 421-426. pl. 27-30. 18 Je 1917. 
