AGRICULTURAL BOTANY. 731 



Effect of asparagin on absci-ption and growtli in wheat, J. J. Skinner and 

 J. II. P.EATTiE (Bill Torrcy Bot. Club, 39 (1912), No. 9, pp. .'i29-Ji37, pi. 1).— 

 During the progress of studies of the organic matter in soils, experiments have 

 been carried on with a number of organic compounds to determine their effect 

 on plant growth. In the present paper an account is given of experiments on 

 the effect of asparagin on the growth of wheat seedlings in culture solutions 

 containing nutrient salta 



When the plants had grown for several days it was noticed that the asparagin 

 cultures were better developed, the seedlings having broader leaves and longer 

 and better developed roots. The effect of asparagin was more marked in the 

 cultures containing jjotash and phosphate than in those which contain potash, 

 phosphate, and nitrate. 



This led to studies under control conditions which indicated that asparagin 

 can be utilizetl for plant synthesis. The effect of the asparagin decreased with 

 increasing quantities of nitrate, so far as additional effect on growth is con- 

 cerned, but it was found to have a conserving effect on the nitrate left in the 

 solution during tlie time the i)lants were growing. 



Studies on the carbohydrates and nitrogen-containing bodies in grape 

 leaves, N. T. Deleano {Iloppc-Sci/Icr's ZtscJir. Physiol. Chem., 80 {1912), No. 

 1, pp. 19-9Jt). — In continuation of previous work (E. S. R., 25, p. 523), the 

 author reports that by analysis of dried grape leaves gathered in September 

 he was able to demonstrate the presence therein of dextrose, levulose, inosit, 

 glutamin. and cholin. but not of sucrose, amino acids, alloxuric bases, histidin, 

 arginin, or betain. A bibliography is appended. 



Phosphoric acid and nitrogen in alcoholic extracts of leaves, J. Seissl 

 (Ztftchr. Lamho. Versuchsic. Osterr., 1/f (1911), No. 6, pp. 886-893; ahs. in Jour. 

 Chem. ^oc. [London], 102 {1912), No. 593, JI. p. 288).— The author's analyses 

 of leaves of horse chestnut, maple, oak, mock orange, and knotweed made 

 monthly during the growing season showed a fairly constant decrease in total 

 phosphoric acid and nitrogen, this diminution being usually more marked in 

 the older leaves. The ratio of phosi)horus to nitrogen also usually showed a 

 decrease, notably in case of horse chestnut and especially just before leaf fall. 



The influence of phosphates on the post-mortem respiration of plants, 

 W. Zaleski and Elisabeth Marx {Biochcm. Ztsch., //5 {1912), No. 1-2, pp. 

 1-6). — Continuing previous studies (E. S. R., 26, p. 729), the authors experi- 

 mented with grain and pea seeds, pulverized and kept for varying periods in 

 solutions of acid, alkaline, and neutral reaction. 



It was found that, in general, acids decreased and alkalis increased the evolu- 

 tion of carbon dioxid. The latter effect, occurring (as in case of edestiu) in 

 absence of hydroxyl, is pointed to as an obstacle to acceptance of the views of 

 S. Kostytschew and A. Scheloumow (E. S. R., 26, p. 627). 



It is claimed that some part is played by the phosphates contained in the 

 seeds tested. It is suggested also that the effect of alkaline phosphates is in 

 part due to the protection given by the alkalinity against the depressing effect 

 of acid-reacting substances (as casein) on the evolution of carbon dioxid, thus 

 favoring a greater net result as regards this product. 



Contribution to the study of circulation. Studies on the sweet potato 

 (Ipomcea batatas), B. H. A. Groth {New Jersey Stas. Rpt. 1910, pp. 283-286. 

 pis. 2, flg. 1). — In continuation of a previous report (E. S. R.. 25, p. 431), an 

 account is given of the circulation in the sweet potato as influenced by the root- 

 ing of the plants at the nodes. In addition to this work, an investigation with 

 the object of tracing the movement of reserve starch in the circulation of a 

 many-rooted sweet potato plant was begun. It was found that the storage 

 starch in a sweet potato plant with the normal direction of the water current is 



