326 
Physiologie. 
Armstrong, H. E. and E. F., Studies on Enzyme Action. 
X. The Nature of Enzymes. (Proc. Roy. Soc. London, Ser. B., 
Vol. 79. p. 360—365. 1907.) 
An account of the general point of view indicated by this series 
of studies in enzyme action. 
The authors’ recent work shows that the correlation of specific 
enzymes to specific classes of hydrolytes is closer than at first reali- 
sed. Maltase does not really hydrolyse «-galactosides, nor emulsin 
/2-galactosides as they were held to do in papers III and V respecti- 
vely, but maltase is specific to «-glucosides and emulsin to ß-glu- 
cosides. 
Careful work with very pure substances shows that only these 
special hexoses which result from hydrolysis of a given biose have 
the power of inhibiting that particular hydrolytic process. 
Invertase seems to have a specially complicated relation of con- 
figuration to cane-sugar which cannot be cleared up tili the Consti¬ 
tution of cane-sugar is established. As both fructose and glucose inhibit 
its action the enzyme must adapt itself to both sections of this biose 
and so may be classed as a biase. The bioses lactose and maitose 
differ in that they are hydrolysed by enzymes which also act on 
the corresponding simple glucosides, monases. 
As regards the formation of enzymes it is conceivable that a 
biase may be hydrolysed to a manase. The sucroclastic enzymes are 
probably the result of such proteoclastic action; hence the great 
differences in the enzymes of extract of dried yeast prepared at 
different temperatures. 
In lipoclastic and proteoclastic enzymes the ränge of action is 
much wider, for lipase acts on many ethereal salts and trypsin on 
synthetic polypeptides. 
Presumably lipase in all cases attacks a specific radicle such as 
— CO — O — common to all its hydrolytes, and trypsin attacks the 
essential radicle of the amino-acids. 
Bertrand’s work on the limits of the oxidising power of Bacte- 
terium xylinum shows that specific configuration t has its effect among 
oxidases also. F. F. Blackman. 
Becquerel, P„ Sur un cas remarquable d’autotomie du 
pedoncule floral du Tabac, provoque par le traumatisme 
de la corolle. (C. R. Acad. Sc. Paris. 25 Nov. 1907.) 
Au cours d’experiences sur la fecondation des fleurs du Tabac, 
Paul Becquerel a constate que si l’on sectionne la corolle de fleur de 
tabac non fecondee, le pedoncule se detache au bout d’une 
quinzaine de jours et la fleur tombe en laissant une cicatrice sur 
l’axe d’inflorescence. L’ablation des sepales, des etamines ou du 
stigmate ne provoque pas la chute de la fleur. Aussitöt apres la 
fecondation, la mutilation de la corolle est sans effet, le pistil con- 
tinue son evolution en fruit. Pour provoquer la chute de la fleur 
non fecondee il suffit de couper la corolle ä la moitie de sa hauteur. 
Ces faits montrent une relation etroite entre la corolle, l’ovaire et 
le ddveloppement du pedoncule. Tant que l’ovaire n’est pas feconde, 
la presence de la corolle et son integrite sont absolument necessaires 
ä la croissance du pedoncule. Jean Friedei. 
Caldwell, R. J. and S. I. Courtauld. Studies on Enzyme action. 
