490 INDEX TO AMERICAN BOTANICAL LITERATURE 
Orton, C. R. Seed-borne parasites—a general consideration of 
the problem. Science II. 59: 530-546. 20 Je 1924. 
Palmer, E. J. Two interesting ferns from Arkansas. Am. 
Fern Jour. 14: 39-41. ‘“‘Ap-Je” 12 Jl 1924. 
Pax, F., & Hoffmann, K. Euphorbiaceae-Crotonoideae-Acaly- 
- pheae-Acalyphinae. Euphorbiaceae-Additamentum. VII. 
Pflanzenreich 47: 1-231. 16 My 1924. 
Including new species from tropical America. 
Perkins, A. T. A note on the nodulation of soy beans. Soil 
Sci. 17: 449-456. Je 1924. 
Perkins, A. T. The effect of several mineral fertilizers upon 
the nodulation of Virginia soy beans. Soil Sci. 17: 439-447. 
Je 1924. 
Pessin, L. J. A physiological and anatomical study of the 
leaves of Polypodium polypodioides. Am. Jour. Bot. 11: 
370-381. f. 1-2-+ pl. 21. 28 Je 1924 
Petrak, F. Mykologische Notizen VII. Ann. Myc. 22: 1-182. 
1924. 
Including a number of new species and genera from North America. 
Piper, C. V. New flowering plants of the Pacific Coast. Proc. 
_ Biol. Soc. Wash. 37: 91-95. 21 F 1924. 
Including new species in Iris (1), Arabis (1), Cardamine (1), Astragalus 
(1), Godetia (1), Lappula (1), Allocarya (3), Crytantha (1), Valeriana (1). 
Popenoe, W. Economic fruit-bearing plants of Ecuador. 
Contr. U.S. Nat. Herb. 24: i-ix, 101~134. pl. 34-49. 1924. 
Ramsey, G. B. Sclerotinia intermedia n. Sp., a cause of decay 
of salsify and carrots. Phytopathology 14: 323-327. f. 
J-STPk 23....2t, Ih 1004. i 
Reed, G. M. The smuts of cereals; their nature, economic im- 
portance, and the significance of recent discoveries. Brook- 
lyn Bot. Gard. Record 13: 103-124. J. 277.5 Jl 1924. 
Reid, M.E. Quantitative relations of carbohydrates to nitrogen 
in determining growth responses in tomato cuttings. Bot. 
Gaz. 77: 404-418. f. 1-8. 16 Je 1924. 
