BOTANY. 311 



tyrosin arc both considered simple products of the decomposition of 

 allHiminoids. In SaUcornia herhacea neither usparag'in nor tyrosin 

 was found. In the leaves of Rohiniapseudacacla there was present 

 small amounts of asparagin but no t3a-osin, while in the leaves of 

 Dahllarar!ah!lis in August neither asparagin nor tyrosin was present. 



A contribution to the study of nitrogen assimilation by legumes, 

 LuTOSLAWSKi {CoitU. Agi'., 1S99, Oct., jk (J8S; ah.-i. hi A/m. A(/7vn., 

 26 (1900), JVo. 8, pp. 4-^5, 4-^6). — An attempt was made to study the 

 fixation of nitrogen by leguminous plants at different stages of their 

 growth. The plants selected for the experiment were peas, and were 

 grown in pots which contained 6 kg. of soil from a field where peas 

 had been grown the previous year. Mineral fertilizer composed of 

 kainit, superphosphate and nitrate of soda, 1.277 gm. per pot, was 

 added to the soil. The different phases of growth recognized were (1) 

 from the beginning of germination until the period just preceding flow- 

 ering, at which time the plants bore from 8 to 10 leaves; (2) at the 

 beginning of flowering; (3) at full flower; (1) at the falling of the 

 flowers; and (.5) at maturity. The total increase for the peas grown 

 in pots receiving no nitrogenous fertilizer for the different periods 

 was 1, 1.65, 3.11, 5.17, and 3.10 per cent. The corresponding num- 

 bers for the peas which had received nitrogenous fertilizers were 0.145, 

 1.89, 2.95, and 2.20 per cent, the abilit}^ to assimilate nitrogen in the 

 case of the plants receiving fertilizers not having manifested itself in 

 the first period. 



Further observations on the nature and functions of the nod- 

 ules of leguminous plants, Maria Dawson (Phil. Tran^. Roy. Soc. 

 [London], 1900, pp. 51-07, pU. 2; ahs. in Proe. Roy. Soc. [Pondon], 

 66 {1900), Wo. 425, 2>p- 63-65). — In continuation of a previous paper 

 (E. S. R. . 11, p. 25), the author reports on the morphology and nature 

 of the organisms occurring in the root tubercles of a number of species 

 of leguminous plants. 



A further study of the morphology leads to the conclusion that no 

 definite line of distinction can be drawn l^etween genera in which fila- 

 ments occur in tubercles and those in which they have not yet been 

 observed. Some peculiar anatomical characters were noted in some of 

 the tubercles, which are to be studied further. In the study of the 

 organisms of Pesmodiimi gyrans it was ascertained that the formation 

 of X and Y forms arises by distinct lateral branching of the straight 

 rods. After 12 to 11 daj's' culture, the individual long rods tend to 

 l)reak up into small ones, and the branched forms become disjointed in 

 a similar manner. 



A general study of these organisms and parallel cultures of Nitragin 



compared with pure cultures from Pisum tubercles shows that they all 



grow readily on gelatin or agar media containing an extract of pea 



stems, asparagin, and sugar, but ver}'^ slowlj^ on broth gelatin. They 



8873— No. 1 2 



