94 



NATURE 



[May 25, 1893 



in length, in which the electrical elements were already well 

 developed, the electric nerve-cells were large and conspicuous, 

 so that sections through the cord in the region of the electric 

 organ presented quite a different appearance from sections 

 through the root ot the tail, where no change had taken place 

 in the cells of the anterior horn. 



May 4. — "On the Differential Covariants of Plane Curves, 

 and the Operators employed in their Development." By 

 R. F. Gwyther, M.A., Fielden Lecturer in Mathematics, 

 Owens College, Manchester. Communicated by Prof. Horace 

 Lamb, F. R.S. 



"Oil the alleged Incre.ise of Cancer." By George King, 

 F.I.A., F.F.A., and Arthur Newsholme, M.D., M.R.C.P. 

 Communicated by Dr. J. S. Bristowe, F.R.S. 



The general result is that the supposed increase in cancer is 

 only apparent, and is due to improvement in diagnosis and 

 more careful certification of the causes of death. 



Chemical Society, April 20th.— Dr. Armstrong, president, 

 in the chair. The following papers were read : — A contribu- 

 tion to the chemistry and physiology of foliage leaves, by H. T. 

 IJrown and G. H. Morris. This paper deals with the occurrence, 

 relations .and physiological significance of the starch, diastase 

 and sugars contained in foliage leaves. The first part relates 

 10 the starch and diastase of leaves, and the second treats of the 

 sugars of the leaf. A bibliography of the subject is appended. 

 Ttie work originated in an attempt to discover the explanation 

 of the conditioning effect of " dry-hopping;" viz., the addition 

 of a small amount of dry hops to finished beer. This was ulti- 

 mately traced to the presence in the hop strobiles of a small, 

 but appreciable, quantity of diastase, sufficient to cause slow 

 hydrolysis of the non-crystallisable products of starch-transfor- 

 mation left in the beer, and to reduce them to a condition in 

 which they can be fermented by the yeast. The authors were 

 then led to enquire into the first formation of starch in the 

 chloroplasts of the foliage leaf, the mode of its dissolution and 

 translocation in the plant and the nature of the metabolised 

 products ; the results obtained are antagonistic to the assump- 

 tion made by Sachs, that all the products of assimilation at 

 some time take the form of starch. Only a small portion of 

 the assimilated material exists at any one time as starch. The 

 fluctuations in the amount of starch in leaves under various 

 conditions were also determined. Wortmann's recent denial 

 that diastase plays any part in the dissolution and translocation 

 of starch in leaves is incorrect ; the authors prove that, instead 

 of leaves containing little or no diastase every leaf examined by 

 them contained sulificient diastase to transform far more starch 

 than the leaf can have contained at any one time. The dif- 

 ference between the author's and Wortmann's results is chiefly 

 due to the faulty method of examination employed l)y the latter. 

 The products of the hydrolysis of starch l)y leaf diastase are 

 identical with those formed by malt-diastase, maltose having 

 been directly separated from the leaves ; leaf-diastase is not 

 able to convert maltose into dextrose, but the leaf contains an 

 enzyme capable of inverting cane-sugar. The amount of 

 diastase present varies greatly in different plants, and within 

 narrower limits even varies in the same plant at different times ; 

 it is very high in the case of the Leguminosae. Any conditions 

 which favour a decrease in the leaf-starch result in an increase 

 of the leaf-diastase ; thus a marked increase in diastatic 

 activity is observed with leaves kept in darkness. Contrary to 

 Wortmann's statement, leaf-diastase can attack the starch- 

 granule under certain conditions ; no evidence could however 

 t>e obtained of the disappearance of starch in killed leaves 

 under the influence of the contained diastase, and the authors 

 are led to the conclusion that theyirj/ stage of dissolution of the 

 starch-granule in the leaf is in some way or other bound up 

 with the /;/< of the cell. From expeiiments on the leaves of 

 Tropaolum the authors draw the following conclusions : — 

 Cane-sugar is the first sugar to be synthesised by the assimila- 

 tory processes. This sugar accumulates in the cell-sap of the 

 leal-parenchyma whilst assimilation is proceeding vigorously, 

 .and when the concentration exceeds a certain point starch com- 

 mences to be elaborated by the chloroplasts at the expense of 

 the cane-sugar. This starch forms a more stable reserve 

 material than the cane-sugar, and is only drawn on when the 

 latter more readily metabolised substance has been partially 

 used up. Cane-sugar is translocated as dextrose and levulose 

 and the starch as maltose. From the invert-sugar derived 

 from the cane-sugar, the dextrose is more readily used up for 



NO. 1230, VOL. 48] 



the respiratory processes, and possibly also for the new tissue- 

 building, than is the levulose ; hence in a given time more 

 levulose than dextrose must pass out of the leaf into the stem. 

 The reading of this paper w.as followed by an interesting dis- 

 cussion in which the President, Mr. Thisellon Dyer, Dr. D. H. 

 Scott, Prof. Green and Dr. Lauder Brunton took part. — The 

 interaction of alk.ali cellulose and carbon disulphide : cellu- 

 lose thiocarbonates, by C. F. Cross, E. J. Bevan and 

 C. Beadle. The maximum number of hydroxyl groups 

 in alkali cellulose appears to be four, expressing cel- 

 lulose as C,2H„„0]„. By the interaction of alkali cellulose 

 and carbon disulphide, cellulose thiocarbonates result ; these 

 products, when treated with water, swell enormously and re- 

 generate cellulose. F"rom a study of a large number of these 

 thiocarbonates the authors are led to assign to them the formula 



/OX 

 CS<^ , where X is the cellulose residue, a radicle of variable 



^SNa 

 dimensions. The thiocarbonates yield solutions of extraordinary 

 viscosity. — Sulphocamphylic acid, by W. H. Perkin, jun. On 

 heating Walters' sulphocamphylic acid, a monobasic acid, 

 C<,H,402 distils ; on dissolving this in sulphuric acid sulphocam- 

 phylic acid seems to be regenerated. By oxidation with perman- 

 ganate the latter yields a dibasic acid, CigHojO-, which on reduc- 

 tion gives another dibasic acid, CigHojO^.. The substance of the 

 composition CigHsoO. yields, on hydrolysis, hydroxymetaxylene- 

 carboxylic acid (CO.,lI : Me : Me : OH = 1:2:4:5) A 

 number of salts and derivatives of the above substances a:e de- 

 scribed. — Magnesium diphenyl, by Lothar Meyer. In reference 

 to a recent note by Hodgkinson (Nature, this vol., p. 22) the 

 author states that magnesium diphenyl has been recently pre- 

 pared in his laboratory ; it is a voluminous powder and is spon- 

 taneously inflammable. The formation of pyridine derivatives 

 from unsaturated acids, by S. Ruhemann. Ethyl methyldicarboxy- 

 glulaconate yields methylmalonamide and ethyl amidoethylene- 

 dicarboxylate with aqueous ammonia ; with phenylhydrazine it 

 gives ethyl raethylmalonate and the ammonium compound of 

 ..CO.C.COOEc 



the pyrazolon PhN 



Ethyl mpthylglutaconate 



NH.CH 



gives /8-methyl-oa'-dihydroxypyridine with aqueous ammonia and 

 ;3-picoline onreduction with zinc dust. Similar reactions hold in 

 the cases of the higher homologues of these two subst.inces. 

 Chlorinated phenylhydrazines. Part n., by J. T. Hewitt. Or- 

 thochlorophenylhydrazine does not yield a urazole when heated 

 with biuret ; both the meta- and para-isomerides give urazoles 

 and their hydrochlorides yield semicarbazides with potassium 

 cyanate. A number of other compounds are described. — The 

 oxidation of tartaric acid in presence of iron, by H. J. H. 

 Fenton. On adding a small quantity of hydrogen peroxide to a 

 solution of tartaric acid containing a trace of ferrous salt, a 

 yellow colour is produced which changes to violet on adding 

 alkali. The substance which gives the colour with ferric salts 

 seems to be represented by the formula C^H^Oj ; it is crystal- 

 line .and behaves as a powerful reducing agent. The author is 

 still engaged in its examination. — The inertness of quicklime, 

 by V. H. Veley. The author is still making experiments on 

 the velocity of reaction between lime in various states of hydra- 

 tion and sulphurous and carbonic anhydrides at different tem- 

 peratures. — The products of the interaction of tin and nitric acid. 

 by C. H. H. Walker. This investigation is a continuation of 

 the work of Veley on the conditions of the interactions of metaU 

 .and nitric acid. The whitish substance formed by the action of 

 fairly concentrated nitric acid on tin seems to have the composi- 

 tion Sn(N03) (OH)3 —Interactions of thiourea .and some haloid 

 derivatives of fatty acids, by A. E. Dixon. Thiourea reacts 

 with dichloracetic acid, yielding thiohydantoic acid and ulti- 

 mately thiohydantoin in accordance with the following equa- 

 tion : — 



S — CH3 

 2CSN2H. -f CHCI.,.COOH = Nil : C( I 



\nH.CO, HCl 

 -f HCI -f S -f HjO + CN.NHo. 



a-monochlor (or brom) propionic acid interacts similarly with 



thiourea, giving methylthiohydantoin ; on boiling this substance 



with hydrochloric acid it yields /3-methyIdioxythiazole 



NH.CO 



CO. I . 



^S -CHMe 



