INDEX TO AMERICAN BOTANICAL LITERATURE 217 
Lipman, C. B. A contribution to our knowledge of soil relation- 
ships with Citrus chlorosis. Phytopatholhgy 11: 301-305. 
9 D Ig21. 
Loeb, J. The quantitative basis of the polar character of re. 
generation in Bryophyllum. Science II. 54: 521, 522- 
25 N 1921. 
Long, C. A. E. Some rare plants from Knox County, Maine. 
Rhodora 23: 198, 199. 15 D 1921. 
Lyon, C. J. Comparative studies on respiration, XVIII. 
Respiration and antagonism in Elodea. Am. Jour. Bot. 
8: 458-403. f, I, 2" 10° 104k: 
Macoun, J. M., & Holm, T. The vascular plants of the arctic 
coast of America west of the 1ooth meridian, collected by 
the Canadian Arctic Expedition, 1913-18. Rep. Canad. 
Arctic Exped. 1913-18. 5A: 5-25. pl. 1-3. 14 O 1921. 
Magrou, J. Symbiose et tuberisation. Ann. Sci. Nat. Bot. X. 
3: 181-275. pl. 1-9 + f.-1-9. N 1921. ' 
Mains, E. B. Unusual rusts on Nyssa and Urticasirum. Am. 
Jour. Bot. 8: 442-451. f. 1-6. . 19 D 1921. 
Includes A plospora, gen. nov. 
Marsh, C. D., & Clawson, A. B. The Mexican whorled milk- 
weed (Asclepias mexicana) as a poisonous plant. U. S. 
Dept. Agr. Bull. 969: 1-16. pl. 1-3 + f. 1. 6O 1921. 
Marsh, C. D., Clawson, A. B., Couch, J. F., & Marsh, H. West- 
ern sneezeweed (Helenium Hoopesii) as a poisonous plant. 
U.S. Dept. Agr. Bull. 947: 1-46. pl. 1,2 +f. 1-5. 1101921. 
McWhorter, F. P. Destruction of mosses by lichens. Bot. 
Gaz. 72: 321-325. pl. 13. 15 N 1921. 
Mead, C. W. Indian corn or maize. Nat. Hist. 21: 408-413. 
O 1921. [Illust.] - 
Menzies, D. Sir Archibald Menzies, R. N. Gard. Chron. 
702 324. 24 D 1921. 
Merrill, E. D. Review of the new species of plants proposed 
by N. L. Burman in Flora Indica. Philipp. Jour. Sci. 19: 
329-388. S 1921. 
