32 EXPERIMENT STATION EECORD, 



toes growu on the plats which had received phosphatic slag auuually for a 

 series of years were very scabby, although the seed had been treated with for- 

 malin before planting. 



In the series of experiments comitaring manure alone with manure and potash 

 it was found that manure alone gave the larger yield of hay. The addition of 

 potash to an average corn fertilizer increased the yield of hay as compared 

 with that obtained with the fertilizer not so reinforced. 



In the experiments comparing sodium nitrate, dissolved boneblack, and 

 muriate of potash, it was shown that potash was the dominant constituent. 

 Nitrogen was least efficient in increasing the yield of com and soy beans. 



The results of experiments in top-dressing grass lands mth barnyard 

 manure, wood ashes, and a mixture of bone meal and muriate of potash were 

 inconclusive. 



In a comparison of winter and spring applications of manure to grass land 

 the results were slightly better w'ith the spring application. 



The direct assimilation of inorganic and organic forms of nitrogen by 

 higher plants, H. B. Hutchinson and N. II. J. Miller {Centbl. Bakf. [etc.], 

 2. Aht., 30 (1 )11), No. 21-24, pp. 513-547, 2>Js. 2, figs. 2; ahs. in-Jovr. Chem. 8oc. 

 [London], 100 {1911), No. 588, II, p. 920). — A review of previous investigations 

 on this subject is given, showing the direct assimilation of ammonium salts by 

 beans, corn, and probably other plants; that various plants are capable of 

 directly assimilating nitrites from dilute solutions; that only negative results 

 as regards assimilation have been obtained with amidosulphonic acid, 

 hydroxylamin, diamid, and azoimid ; and that while the great majority of 

 organic compounds have given negative results, more or less satisfactory evi- 

 dence of assimilation has been obtained with methylamins, amylamins. 

 allylamins, dimethylamin. acetamid, cholin, betain, leucin, urea, dicyandiamid, 

 aspartic acid, asparagin. glutamin, allantoin, uric acid, hippuric acid, tyrosin, 

 and humic acid. The gains of nitrogen have, however, generally been very 

 small and in many cases negative results have been obtained by other in- 

 vestigators. 



In sand and water-culture experiments under carefully controlled conditions with 

 wheat and peas the authors obtained results from which they classify the various 

 substances experimented with according to their availability as sources of nitrogen 

 as follows: "(1) Readily assimilated — ammonium salts, acetamid (CH3.CO.NH2), 



urea (CO<^tt-J, barbituric acid (with calcium carbonate) ( C0<t^rT'QQ>CH2 ), 



alloxan ( CO<!fvjTT'/-iQ>CO ), hnmates; (2) assimilated — formamid (H.CO.NHj), 

 glycin (NH2.CH0.COOH), (a) aminopropionic acid (CH3.CH(NHo).C00H), guani- 

 din hydrochlorid ('NH:C<^y-), cyanuric acid (cO<JJ2-^q>NhY oxamid 



(co'nhO' ^^'^^""^ aspartate (ch^cOOH^*^^)' P^P^o"; (3) doubtful— trimethy- 

 lamin, para-urazin ( CO<iy^TT't^jT>CO j, hexamethylenetetramin; (4) not assimi- 

 lated — ethyl nitrate, propionitrile, hydroxylamin hydrochlorid, methyl carbamate; 

 (5) toxic — tetranitromethan. The above grouping is, of course, only provisional 

 and applies only (except as regards ammonium salts) to peas. It is possible that 

 other plants may be able to utilize some of the substances which with peas have 

 given negative results." 



The special apparatus devised for sterilizing the seed and growing the plants 



under sterile conditions in these experiments is described and a very complete 



bibliography of the subject is given. 



