15(j REPORTS ON THE STATE OF SCIENCE. 



the -CHOH- and -NH-CHOH" groups reduction, giving rise eventually 

 to chains of the type 



I I I 



-CO-CHo-CH-OH-NH-CH2-CH-NH-CF2CO,H, 



which are regarded as forming the unit of the proteid molecule. 



Gautier's explanation of the formation of proteids from formaldehyde 

 and prussic acid as primary materials is purely speculative, and has at 

 present no experimental evidence to support it. Yet there is much to 

 be said for his view that prussic acid is an important factor in plant 

 metabolism, and support for it is found in the fact that the acid is widely 

 distributed in plants, and that Treub's botanical researches on Panghim 

 edule and Phaseolus lunalus indicate that prussic acid is concerned in the 

 metabolism of these plants. The fact that prussic acid is not obtainable from 

 all plants does not invalidate this theory, since the acid may be a plastic 

 substance which is immediately utilised in the metabolism of the plant. 



Hebert has brought forward a series of observations made on the 

 columbine [Aquilegia vulgaris) which lend some support to Gautier's 

 view as to the method of production of prussic acid. In this plant 

 prussic acid is obtainable from the stems, leaves, and unopened flower- 

 buds, but not from the roots. In the fully developed flowers none is 

 produced by the calyx or stamens, neither of which contain chlorophyll, 

 but considerable quantities can be obtained from the ovary, which is 

 chlorophyllaceous. From these results Hebert draws the conclusion that 

 in Aquilegia vulgaris the formation of prussic acid is dependent on the 

 formation of formaldehyde. 



Treub, on the contrary, has shown that in Phaseohcs lunatus and 

 Pangium edule the production of the acid is not directly dependent on 

 the energy derived from light, but is influenced mainly by the supply of 

 sugar available. This observation has led Treub to modify Gautier's 

 theory, and to suggest that the reduction of nitric acid in the cell-sap is 

 brought about by the action'of a sugar on the acid. 



Professor Meldola in his recent presidential address to the Chemical 

 Society, ' The Living Organism as a Chemical Agency,' ' says, in reference 

 to the theories of Bach and Gautier (wrongly attributed to Htjbert in the 

 address) that on careful consideration these do not appear very plausible, 

 and that for these views ' there is at present practically no evidence either 

 from the physiological or chemical side.' This statement is perhaps 

 rather stronger than is warranted by the facts of the case, and a fairer 

 position is that taken up by Treub, who concludes his memoir on 

 Phaseolus lunafAis by saying : ' II serait premature de vouloir expliquer, 

 en partant de I'acid cyanhydrique, I'origine des differents corps reconnus 

 dans la plante comme prrcurseurs des substances albuminoides. Le 

 moment d'entrer dans des discussions de cette nature ne sera venu que 

 lorsque les vues hypothetiques emises ici auront ete confirmees par les 

 resultats de nouvelles recherches, enterprises sur d'autres plantes.' 

 Czapek, in his recently issued ' Biochemie der Pflanzen' (vol. ii., p. 259), 

 says : ' Die ganze Blausjiurefrage bedarf eines griindlichen umfassenden 

 Studiums, da es sich unstreitig um physiologisch wichtige Stofl'wechsel ■ 

 vorgange handelt, und die Bildung cyanhydrin- oder nitrilartiger Sub- 

 stanzen mugUcherweise im Chemismus der Zelle eine bedeutungsvolle Roll^ 

 .spielt.' 



> Jpurn. Chem. Soc, 1906, 89, 7G5. 



