BOTANY. 19 



Studies on tlie formation of nitrogenous compounds in plants, A. Emmerling 



(Landiv. ler.f. Stdt., r>4 {WOO), No. S-4, pp. 215-281; abs. in Arm. Agron., ;t', {WOO), 

 No. 10, pp. 517-522). — The author conducted a series of investigations on the forma- 

 tion of nitroj^enons bodies in different j)arts of the plant during various stagi's of 

 development. The plant chosen for the experiments was Viciaf((ha. Analyses were 

 made on (I different dates, representing stages in the development of the plant from 

 the day it had developed 'A or 4 leaves to its maturity. 



In the first and second periods, the dry matter of the plant was at tlu' niinimum. 

 The leaves contained their minimum content of total nitrogen, and active nitrogen 

 assimilation had not yet begun. The roots, stems, and leaves contained about the 

 same (piantities of amido acids. Combined nitrogen was most abundant in the 

 leaves and buds. The third period was when the plants were in liowcr, and at this 

 time nonproteifl nitrogen was found abundantly in all parts of the Hower, and amido 

 acids exceeded all other nitrogenous compounds in the leaves. During the second 

 to the fourth period, inclusive, the nitrogenous bodies increased aV)out three times. 

 The leaves maintained their relative excess over the other parts. At the end of 

 this period assimilation was at its height. Amido acids were formed more actively 

 than bases, and the nitrogenous content of the roots was slowly increased. At the 

 end of the period, some fruits had been formed in which the proportion of nonpro- 

 teid and total nitrogen in the seeds and hulls was about eciuaj. During the fifth 

 period there was a marked increase in the dry matter of the fruits, and much nitro- 

 genous matter was requii-ed by the seeds. The daily increase in nitrogen at this 

 period was greater than in the preceding ones, and there was an active consumption 

 of inorganic nitrogen for the formation of albumen. The fruits at the end of this 

 period contained nonproteid bodies as their reserve material, and basic nitrogen was 

 more abundant in the seeds than in the hulls. The quantity of nonproteids at this 

 time was about the same in the leaves, hulls, and seeds. In the sixth period the 

 dry liiatter of the fruits increased rapidly, and the daily increase of nitrogen attained 

 its maximum. At this time the dry matter of the leaves about equaled that of the 

 fruits. The proteid nitrogen increased in the seeds and hulls, while the nonproteids 

 increased but little. Amido acids diminished very appreciably in the leaves and 

 fruits. During the sixth and subsequent periods, until maturity, there was a gradual 

 increase in the dry matter of the seeds. An increase in the nitrogenous constituents 

 was found only in the seeds, and it was made at the expense of the nitrogen of the 

 leaves, stems, hulls, etc. The amido acids in the seeds are transformed during the 

 period of ripening, and they are said to be employed for the develoinnent of the 

 seeds. The leaves and hulls seemed to act as reserve organs for the amids. At 

 maturity the amid compounds decreased throughout the entire plant. 



An extensive review of the literature relating to the subject is given, and the 

 methods of cxjjerimentation are described in detail. 



Albuminous substances and their transformations in the plant in connec- 

 tion with respiration and assimilation, D. N. PrianisHiMkov {Izr. .1/o.scom' <SW.sA-. 

 KIki:. IiisI., .7 ( /.s'.'y.'y), pt. .i, ji/t. VcV.^-./.s'.v). — Descriptions are given of experiments with 

 Pixnm KdlJrnin, Viclaf(ih((,-Aw\ Liipiunx hilmx, lasting for 18 days and made in order 

 to study the connection between tlie energy of the decomposition of the albuminous 

 substances and the age of the plants. The author concludes: 



(1 ) The process of the decomposition of the albuminous substances in the vegeta- 

 tion of seeds has its maxinunn j)eriod, which is characterized by a high curve. 



(2) The process of the accunudation of asparagin is represented by a similar curve, 

 its maximum coinciding with the maximum of the former curve. 



(3) r>oth curves reach their highest points a few days earlier than the curve of th« 

 respiration of carbonic acid. 



(4) At tlu- end of the period of vegetation, the energy of the accumulation of 



