INDEX TO AMERICAN BOTANICAL LITERATURE 597 
Nichols, G. E. Summer evaporation intensity as a determining factor 
in the distribution of vegetation in Connecticut. Bot. Gaz. 56: 
143-152. 14 Au 1913. 
Orton, W. A. The development of disease-resistant varieties of plants. 
IV°. Conférence Internat. Génétique, Paris 1911: 247-265. f. I-9. 
1913. 
Ostenfeld, C. H. Marine plankton from the East-Greenland Sea (W. 
of 6° W. Long. and N. of 73° 30’ N. Lat.), collected by the ‘‘ Dan- 
mark-expedition” 1906-1908—I. List of diatoms and flagellates. 
Meddelelser om Grénland 43: 259-285. f. I-11. 1910. 
Ostenfeld, C. H., & Lundager, A. List of vascular plants from north- 
east Greenland (N. of 76° N. Lat.), collected by the “ Danmark- 
expedition”’ 1906-1908. Meddelelser om Grénland 43: 1-32. fl. 
1-6 +f. I-3. 1910. 
Ostrup, E. Diatoms from northeast Greenland (N. of 76° N. Lat.), 
collected by the “ Danmark-expedition”’ 1906-08. Meddelelser om 
Grénland 43: 195, 196-256. pl. 13, 14. 1910. 
Pammel, E. C., & Clark, C. Studies in variation of red clover. Proc. 
Iowa Acad. Sci. 18: 47-54. 1911. [Illust.] 
Pammel, L. H. Some fungus diseases of trees. Proc. lowa Acad. 
Sci. 18: 25-33. 1911. [Illust.] 
Pammel, L. H., & King, C. M. Pollination of red clover. Proc. lowa 
Acad. Sci. 18: 35-45. 1911. [Illust.] 
Pennell, F. W. Studies in the Agalinanae, a subtribe of the Rhinan- 
thaceae. Bull. Torrey Club 40: 401-439. Au 1913. 
Includes descriptions of 5 new species. 
Prain, D., & Hutchinson, J. Notes on some species of Acalypha. Kew 
Bull. Misc. Inf. 1913: 1-28. f. 1-46. Mr 1913. 
Quehl, L. Allerlei aus dem Kakteenkasten. Monats. Kakteenk. 23: 
93, 94- 15 Je 1913. 
Reimer, F. C., & Detjen, L. R. Self-fertility of the scuppernong and 
other muscardine grapes. North Carolina Agr. Exp. Sta. Bull. 
209: 5-23. f. I-13. S 1910. 
Ricker, P. L. Directions for collecting plants. U. S. Dept. Agr. 
Plant Ind. Circ. 126: 27-35. f. 1-5. 10 My 1913. 
Rolfs, P. H., Fawcett, H. S., & Floyd, B. F. Diseases of citrus fruits. 
Univ. Florida Agr. Exp. Sta. Bull. 108: 27-47. f. 10-23. N 1911. 
Rolfe, R. A. Stanhopea convoluta. Curt. Bot. Mag. IV. 9: pl. 8507. 
Au 1913. 
A plant from Colombia, South America. 
