CHEMISTRY. 327 



tlu' pvrimidiu and farl)nliy(lr:U(' ,u:voups are represented l)y thyiniii and hexone, in 

 the latter by uracyl and pentose. 



" (11) Tritico-nucleic acid closely resembles, and may be identical with, the nncleic 

 acid of yeast, since both contain uracyl and a pentose and api)ear to have the same 

 ultimate composition. 



" (12) Tritico-nucleic acid resembles gnanylic acid, in that botli may be represented 

 as complicated esters of a i)liosphoric acid formed by the union of four P(OH )-^ groujis, 

 but otherwise they present marked differences, which indicate different physiological 

 relations. 



"(13) The conception of tritico-nucleic acid as an ester of pentahydroxyl phos- 

 phoric acid suggests a chemical relation that may possibly exist between paranucleie 

 acid and the true nucleic acids, for the organic part of the paranuclein of egg yolk, as 

 one of us has previously shown, has nearly the same composition as that of the organic 

 part of the paranucleo-proteid from which it originated, as is seen when the analyses 

 are calculated PC), fiee. (Four 1*(()II)5 grou])S united by 3 oxygen atoms contain 

 r:0::l:4i). 



" (14) The i)rotein compounds of nucleic acid may be regarded as protein nucleates, 

 those containing but little nucleic acid united with much protein forming the nucleo- 

 proteids, those with much nucleic ai-id and little protein forming the nucleins. The 

 jiroportion in wdiich the protein and nucleic acid unite is determined by the relative 

 proportion of bases and acids present in the solution at any given time." 



The ash constituents of plants, their estimation and their importance to 

 agricultural ehsmistry and agriculture, P>. Tolf.ens (Jour. Lcn/dir., 'lO {190J), 

 Xo. 3, pp. 231-275). — This is a revised re})rint (in (Terman) of an article published in 

 the Record (18, pp. 207, ;!05). 



On the determination of phosphoric acid in plants, G. Sokolov [Zlmr. Opuiiv. 

 A(jr(tn. [.F()(ir. llrpl. Landir.], 2 {I'JOl), Xo. 6, pp. 770-779). — The investigations 

 rei)orted in this article relate especially to the determination of pliosplioric acid in 

 the ash of various kinds of wood. It was found that in case of woods ordinarily 

 yielding an a.^h rich in lime simple incineration is the most satisfactory method of 

 prejiaring material for the determination of i)hosphoric acid. 



The chemical methods of determining- the productiveness of soils as 

 dependent upon phosphoric acid, K. K. Gedroiz (Zhuv. Opuitu. Agruu. [Jour. 

 E.rpt. Liniihr.], 2 (1901), Xo. c, pp. 745-769). — Comparison of results obtained by 

 means of chemical methods with those furnished by pot experiments on a nmnber 

 of different 2:)lants indicate that plants vary so much in their power of taking up 

 phosphoric acid from the same soil that no one solvent can be relied on to measure 

 the availability of this constituent for all plants. The author, however, considers 

 the use of 2 jier cent citric acid jireferable to 2 per cent acetic acid proposed by 

 Bogdanov for determining availal)le j)hosj)horic acid in the soil. 



On the amount of 1 per cent hydrochloric acid required for the digestion 

 of soils for analysis, P. Kossovicii (Zhur. Opuitn. Agron. {_Jour. E.rpt. Ldudir.], 2 

 ( 1901), Xo. 5, pp. 639-642). — Tests of 5 very dissimilar soils using 10 gm. of the soil 

 to 500 cc. and 1,000 cc. of 1 per cent hydrochloric acid, indicate that the smaller 

 amount of acid is not sufficient in all cases, but that 100 times as nmch aci<l as 

 soil should be used. The author reconniiends 50 gm. of soil and 5 liters of 1 i)er 

 cent acid 



On the question of the determination of humus in soils, P. Kossovicn {/Jmr. 

 Opiritn. Agron. [J<mr. Expt. Laiulw.'}, 2 (1901), Xo. 5, pp. 643-646).— The author 

 reports examinations of chernozein soils which show that such soils rarely contain 

 carbonates in sufficient amounts to interfere with the determination of humus by 

 coml)ustion in oxygen. 



The determination of lim and magnesia iix water, A. Grittne]! (Zl.'ivJir. 

 Angew. Chcju., 15 (1902), pp. 847-852; nbs. In Chem. CentbL, 1902, II, Xo. 13, p. 857). — 



