INDEX TO AMERICAN BOTANICAL LITERATURE 219 
Puttick, G. F. The reaction of the F, generation of a cross 
between a common and a durum wheat to two biologic 
forms of Puccinia graminis. Phytopathology 11: 205- 
24%, 04) toot. 
Raber, O.L. The effect upon permeability of polyvalent cations 
in combination with polyvalent anions. Am. Jour. Bot. 
8: 382-385. f.. 1... 14 N -t921. 
Studies of Laminaria. 
Raber, O. L. The effect upon permeability of (I) the same 
substance as cation and anion, and (II) changing the 
valency of the same ion. Am. Jour. Bot. 8: 464-470. f. 7, 2. 
19 D 1921. 
Rangel, E. Nota sobre dois fungos. Arch. Escol. Super. Agr. 
e Med. Veter. 5: 35-40. pl. 3-5. S 1921. 
Oswaldia, gen. nov., and Peniotrichum saccardinum, sp. nov. 
Record, S. J. Figure in wood. Am. For. 27: 611-617. O 
1921. [Illust. 
Rehder, A. Plant nomenclature: more suggestions. Jour. Bot. 
289-294. O 1921. ; 
Reinking, O. A. Fiji disease of sugar cane in the Phillippine 
Islands. Phytopathology 11: 334-337. pl. 15,10. 9D 1921. 
Reinking, O. A., & Groff, G. W. The Kao Pan seedless Siamese 
pummelo and its culture. Philipp. Jour. Sci. 19: 389-437. 
pl. 1-16 + f. 1. O 1921. 
Rendle, A. B..- sta an overlooked genus-name. Jour. Bot. 
Be 261-264. SI 
ludes reprint of the ee publication of this genus and its 3 species 
by aoe in New Orleans Med. & Surg. Jour. 1847: 614-616. 1847. 
Renner, O. Das Rotnervenmerkmal der Onotheren. Ber. 
Deutsch. Bot. Ges. 39: 264-270. 105 1921. 
Richards, B. L. A dryrot canker of sugar beets. Jour. Agr. 
Research 22: 47-52. pl. 4-9. 1 O 1921. 
Roark, E. W. The Septoria leaf spot of Rubus. Phytopath- 
ology 11: 328-333. 9 D 1921. 
Due to Mycosphaerella Rubi, sp. nov. 
