No. 3, October, 1921] PHYSIOLOGY 263 



and nitrogen was reduced to rs of the quantity present in the normal solution. Plants were 

 grown to maturity in each case. The calcium content of both grain and straw is reduced to 

 about 10 per cent of that in the controls by reducing the calcium in the culture solution to 

 1^ the quantity in the complete solution. It is greatly reduced in both grain and straw by a 

 similar deficiency in phosphorus or nitrogen. By reducing the phosphate in the culture 

 solution to rtj of the quantity in the complete solution used as control, the total phosphorus 

 content of the grain is thereby reduced to 46 per cent and that of the straw to 10 per cent of 

 the qiiantity found in the complete solutions. It is slightly reduced in both grain and straw 

 by a similar deficiency in potassium, and is increased by a similar reduction of calcium or nitro- 

 gen. Variations in composition are more pronounced in straw, but in general are similar 

 in both grain and straw. The phosphorus content of both grain and straw is modified by sea- 

 sonal differences except in phosphorus-deficient solutions. The calcium content of the grain 

 is modified by seasonal differences even in calcium-deficient solutions. The calcium content 

 of the straw shows no consistent response to climate. — E. W. Sinnott. 



1620. EspiNO, R. B. A preliminary study of the mineral nutrition of young cotton 

 plants. Philippine Agric. Rev. 13:335-343. 1920. 



1621. Howe, H. E. Some of the new applications of sulfur in agriculture. Sci. Amer. 

 124: 392. 1921. — This is a condensation of an article by J. G. Lipman in a recent issue of the 

 Chemical Age. — Chas H. Otis. 



1622. Meier, Henry F. A., and Clifton E. Halstead. Hydrogen-ion concentration 

 relations in a three-salt solution. Soil Sci. 11: 32.5-351. PL 1, 9 fig. 1921. — Fulcaster wheat 

 was grown for a period of 35 days in water cultures containing potassium dihydrogen phos- 

 phate, calcium nitrate, and magnesium sulphate in varying proportions and having a total 

 osmotic value of 1 atmosphere. The solutions were changed at 3-day intervals and the 

 hydrogen-ion concentration determined at each change. No one combination of the 3 salts 

 gave constantly a maximum yield of tops, roots, or total dry weight in the 3 sets grown at 

 different periods. The cultures giving maximum dry weights exhibited minimum water re- 

 quirements. The hydrogen-ion concentration of acid solutions in which the wheat was grown 

 tended to approach neutrality. There was no apparent correlation between the yield of the 

 plant and the hydrogen-ion concentration, or change in hydrogen-ion concentration. Those 

 degrees of acidity which are just harmful to Actinomyces and Azotobacter have no visible effect 

 on wheat. — W. J . Robbins. 



1C23. Trelease, S. F., and P. Paulino. The effect on the growth of rice of the addition 

 of ammonium and nitrate salts to soil cultures. Philippine Agric. Rev. 13 : 293-313. 1920. — The 

 highest yields were secured when nitrogen was supplied as ammonium sulphate, the next 

 higher in order being with nitrate — calcium nitrate and sodium nitrate. — E. D. Merrill. 



PHOTOSYNTHESIS 



1624. Yap, G. G. A study of the photosynthesis of sugar cane. Philippine Agric. 8: 

 269-276. 1920. — The general conclusions are as follows : The rate of photosynthesis decreased 

 from 10 in the morning to 4 in the afternoon, the leaves being most active from 8 to 10 in the 

 morning; young leaves are more active than old ones; the rate of respiration was apparently 

 less than | that of photosynthesis; high light intensity probably has an indirect relation to 

 the rate of photosynthesis, tending to decrease photosynthetic activity. — E. D. Merrill. 



METABOLISM (GENERAL) 



1625. Delauney, P. Nouvelles recherches concernant Textraction des glucosides chez 

 quelques orchidees indigenes : identification de ces gluosides avec la loroglossine. [The ex- 

 traction of glucosides from certain indigenous orchids and the identification of these glucosides 

 with loroglossin.] Compt. Rend. Acad. Sci. Paris 172: 171-473. 1921. — The glucoside, loro- 



