1019] CONTENTS. Ill 



Page. 



Electric power for nitrogen fixation, Scott 127 



A new fertilizer, "superphosphate of ammonia," Brioux 127 



Solubility and asslmllabllity of calcium phosphates, Lindet and Bruno 128 



Recovery of potasb from iron blast furnaces and cement kilns, Bradley-- 128 



Recovery of potash from kelp, Biggins i_ r > 



Potasb from desert lakes and alunite, Hornsey 128 



Potash from Searles Lake, de Ropp, jr 128 



The Alsatian potash mines and works 128 



Lime, and the liming of soils, llanley 128 



The recovery of ashes and their utilization In agriculture, Pifidallu 129 



AGRICULTURAL BOTANY. 



Ecology, Clements 129 



Experimental evolution in a desert habitat, Tower 12'.) 



Vital statistics of desert plants, shreve 129 



ITant distribution on desert mountains, Shreve ]2'J 



Kate of growth in relation to altitudinal conditions, Shreve 129 



Role of climatic conditions as to vegetation, Livingston and Shreve 130 



Evaluation of temperature of soil as an environmental factor, Cannon 130 



Osmotic concentration of fluids and geographical distribution, Harris 130 



Vegetable saps i: - ,!i 



Developmental and nutritional physiology of some Chlorophycese, Nakano_ 130 



Controlled pollination in Nicotiana, Goodspeed and Davidson 131 



The inheritance of germinal peculiarities. Flowering plants 131 



Analysis of a potato hybrid, Solatium fendleriXS. tuberosum, MacDougal 131 



Mass mutations and twin hybrids of QSnothera <jrandiflora, DeVries 132 



South African Perisporiales. — I, Perisporiacere, Doidge 132 



Dredinales of Andes, based on collections by Dr. and Mrs. Rose, Arthur 133 



Allies of klclayniclla rupeatris in United States, Van Eseltine 133 



FIELD CROPS. 



Farm practices that increase yields in Kentucky and Tennessee, Arnold 133 



Farm practices that increase crop yields in Gulf Coast region, Crosby 133 



Crop systems for Arkansas, McNair 133 



[Tests with held crops and vegetables at the Rhode Island Station] 133 



Effect of crops on each other 135 



Plant propagation 135 



Steam sterilization of seed beds for tobacco and other crops, Beinhart 135 



Relative yields of oats and two-rowed barley in middle Sweden, Tedin 135 



Comparative test with fertilizers, manure, and sewage, 1910-1916, Bolin 135 



Meadow culture tests iu Jutland, 1905-1910, Lindhard 136 



Alfalfa, App 137 



[Utilizing waste land in New Jersey for alfalfa] 137 



Primitive methods of maize seed preparation, Biggar 137 



Cutthroat grass, Panicum combsii, Piper 137 



Glandular pubescence in various Medicago species, McKee 137 



Variety tests with oats in southern and middle Sweden, Akerman 13S 



Potato culture tests in 1917, Lind 138 



Lining and loading cars of potatoes against cold, Bird and Grimes 13S 



Farm practice in growing sugar beets in Colorado, Moorhouse et al 133 



Farm practice in growing sugar beets in Montana, Nuckols and Currier 139 



The beet-sugar industry in the United States, Townsend 139 



The inheritance of glume length in Triticum polonicum, Backhouse 140 



Origin of the Georgia and Alabama varieties of velvet beau, Coe 141 



Variety tests of wheat, Cauthen 111 



Natural cross-polliuation in wheat, Hayes 142 



Natural crossing in wheat, Hayes 142 



Explanation of changes in proportions of hard and soft kernels, Freeman. 142 



Producing bread-making wheats for warm climates, Freeman 143 



Nematode galls in marketing and milling wheat, Coleman and Regan 141 



Have farmers been given a square deal in the Federal standards? Brand- 144 



Federal grain supervision and standards for wheat applied to 1917 crop_ 144 



A comparison of the Federal v. Minnesota grading system, Sanderson 145 



