§ 
INDEX TO AMERICAN BOTANICAL LITERATURE 161 
Burlingame, L. L. Variation and heredity in Lupinus. Am. 
Nat. 55: 427-448. f. 1-3. O 1921. 
Cayla, V. A propos de la qualité du cauotchouc d’Hevea 
brasiliensis, ses variations, leurs causes. Importance 
economique pour la. production de Il’Amazone. Arch. 
Escol. Super. Agr. e Med. Veter. 5: 81-96. S 1921. 
Chace, E. M., Wilson, C. P., & Church, C.G. The composition 
of California lemons. U. S. Dept. Agr. Bull. 993: 1-18. 
f. 1-4. 15 O 1921. 
Chamberlain, C. J. Growth rings in a monocotyl. Bot. Gaz. 
72: 293-304. f. 7-16. 15 N 1921. 
Clark, A. H. A new classification of animals. Bull. Instit. 
Oceanogr. 400: I-24. 20S Iga2l. 
Includes a summary of plant classification. 
Clements, F. E. Drouth periods and climatic cycles. Ecology 
2: 181-188. 3 DD 162i 
Coker, W. C., & Beardslee, H. C. The collybias of North 
Carolina. Jour. Mitchell Sci. Soc. 37: 83-107. pl. 1 +f. 4-23. 
D 1921 
Includes Collybia lilacina, sp. nov. 
Cook, F. C. Absorption of copper from the soil by potato 
plants. Jour. Agr. Research 22: 281-287. 29 O Ig21. 
Cook, M.T. The blossom blight of the peach. Phytopathology 
11: 290-294. pl. 12. 15 N 1921 
Cook, M. T. Falling foliage. Phytopathology 11: 337-339. 
a LY toatl, 
Cook. M. T. Peach yellows oa ae peach. Bot. Gaz. 72: 
250-255. pl. 6, 7. 15 OI 
Cook, M. T. Wilting caused by site trees. Phytopathology 
11: 346. 9 
Cook, O. F. Causes of shedding in cotton. Jour. Hered. 12: 
199-204. f. 3-6. 23S 1921. 
Coville, F. V. Directions for blueberry culture, 1921. U. S. 
Dept. Agr. Bull. 974: 1-24. pl. 1-29. 15 O 1921. 
Creswell, C. F., & Bidwell, G. L. ates of cotton seeds. 
U. S. Dept. Agr. Bull. 948: 1-221. pl. 1+ maps I-11. 105 
1921. 
