INDEX TO AMERICAN BOTANICAL LITERATURE 283 
Hurd, A. M. The relation between the osmotic pressure of Nereo- 
cystis and the salinity of the water. Publ. Puget Sound Biol. 
Sta. 2: 183-193. 5 Mr 19109. 
Irwin, M. Comparative studies on respiration—VI. Increased pro- 
duction of carbon dioxide accompanied by decrease of acidity. 
Jour. Gen. Physiol. 1: 399-403. f. 1, 2. 20 Mr 1919. 
Itano, A., & Neill, J. Influence of temperature and hydrogen ion 
concentration upon the spore cycle of Bacillus subtilis. Jour. Gen. 
Physiol. 1: 421 —428. f. 1, 2. 20 Mr 1919. 
Jagger, I. C. Control of vegetable diseases. Cornell Ext. Bull. 
19: 2915-2936. f. 91-113. Je 1917. 
Lyman, G. R. The unification of American botany. Science II. 
49: 339-345. 11 Ap 1919. 
Lynge, B. Ueber einige Regnellschen Parmelien aus Matteo-Grosso, 
Brasilien. Ark. Bot. 15): 1-4. 1918. 
Parmelia fatiscens and P. coccinea, spp. nov., are described. 
McClelland, T. B. Influence of foreign pollen on the development of 
vanilla fruits. Jour. Agr. Research 16: 245-252. pl. 31-35. 3 Mr 
1919. 
MacDougal, D. T., & Spoehr, H. A. The origination of xerophytism. 
Plant World 21: 245-249. O 1918. 
McDougall, W. B. Development of Stropharia epimyces. Bot. Gaz. 
67: 258-263. f. I-10. 18 Mr 1919. 
Martin, W. H. A comparative study of salt requirements in solution 
cultures for the growth of buckwheat to the flowering stage and to 
maturity. New Jersey Agr. Exp. Sta. Ann. Rep. 38: 419-422. 
1917. 
Matz, J. Algunas observaciones respecto a la Sarna (scab) del citro 
en Puerto Rico. Rev. Agr. Puerto Rico 2: 40, 41. F 1919. 
Matz, J. Enfermedad de la rdiz de la cafia de Azicar. Rev. Agr. 
Puerto Rico 2: 38, 39. F 1919. 
Mousley, H. The orchids of Hatley, Stanstead County, Quebec. 
Ottowa Nat. 32: 144-147. F 1919. 
Murrill, W. A. Trees and children. Jour. N. Y. Bot. Gard. 20: 
61-63. Mr i919. 
Neller, J. R. The influence of the roots of growing plants upon the 
activity of soil microérganisms as indicated by the production of 
carbon dioxide from the soil. New Jersey Agr. Exp. Sta. Ann. Rep. 
38: 414, 415. 1917. 
