July 1904] Index to North American Mycology 183 
Polyporus [Fomes] ponderosus von Schrenk n. sp., on dead 
trees and fallen legs of the Western Yellow or Bull Pine 
(Pinus ponderosus). U. S. Dept. Agr. Bureau PI. Industry, 
Bull. 36:30. PI. VII. 5 May 1903. 
Polyporus ponderosus von Schrenk n. sp. [Cause of “Red Rot” 
of Western Yellow Pine, von Schrenk.] U. S. Dept. Agr. 
Bureau PI. Industry, Bull. 36:30. PI. VII. 5 May 1903. 
Pori a rufitincta Berk & Curt. Grev. 15:25. 1887. [Nomen tan- 
tum. Description, Annie L. Smith.] Jour. Lin. Soc. Botany, 
London, 35:7. 1 April 1901. 
Polyporus variiporus Murrill n. sp., on sticks buried in sandy 
soil in woods. Bull. Torr. Bot. Club, 31 Jan. 1904. 
Populus deltoides, decorticated limbs, host to Anthostomella 
thyridioides E. & E. n. sp. Jour. Mycol. 9:167. Oct. 1903. 
Potato Diseases, see Diesases, Potato , and .... 
Potato Rosette, Studies in. II. [Prevalence, Prevention, Elim¬ 
ination by Rotation, Tomato Rosette.] A. D. Selby. Ohio 
Agr. Exp. Stat. Bull. 145:15-28. figs. 1-4. Nov. 1903. 
Potentilla blaschkeana, host to Phragmidium affine Syd. n. sp. 
Ann. Mycolog 2:30. Jan. 1904. 
Proof of the Identity of Phoma and Phyllosticta on the Sugar 
Beet. Jour. Mycol. 10:2-3. Jan. 1904. [Abstract in Sci¬ 
ence, N. S. 19:172. 29 Jan. 1904.] 
Pseudoperonospora cubensis (B. & C.) Rostowzew n. n. [Pero- 
nospora (Plasmopara) cubensis B. & C.]. Flora od. Allg. 
Bot. Zeit. 92:405-430. 6 Oct. 1903. 
Pseudovalsa canadensis E. & E. n. sp., on dead limbs of Haw¬ 
thorn, Crataegus. Jour. Mycol. 9:224. Dec. 1903. 
Pseudovalsa minima E. & E. n. sp., on Maple bark. Jour. 
Mycol. 9:224. Dec. 1903. 
Puccini a. The Genus. [Nomenclature.] J. C. Arthur. Proc. 
Indiana Acad. Sci. 1902:81-3. 1903. 
Puccinia actinomeridis Magn. n. sp., on Actinomeris squarrosa. 
Ber. Deutsche Bot. Gesell. 19:294. 1901. 
Puccinia albiperidia Arth. [Successful cultures on Ribes cynos- 
bati, and on (?) R. uva-crispa [spermogonia]. Arthur.] 
Jour. Mycol. 10:11. Jan. 1904. 
Puccinia amphigena Diet. [Successful cultures on Smilax his- 
pida. Arthur.] Jour. Mycol. 10:11. Jan. 1904. 
Puccinia andropogonis Schw. [Successful cultures on Pentste- 
mon hirsutus. Arthur.] Jour. Mycol. 10:11. Jan. 1904. 
Puccinia angustata Pk. from Scirpus atrovirens Muhl. [Suc¬ 
cessful cultures on Lycopus americanus. Kellerman.] Jour. 
Mycol. 9:226. Dec. 1903. 
