140 Physiologie. 



deprecates the general acceptance of „dissociation" as explanitory 

 of many reactions. Aiter shortly reviewing Buchner's work 

 on Yeast-enzymes he suggests that possibly Bii ebner was 

 dealing with Systems intermediate in complexity between enzymes 

 proper and protoplasm itself, in which endotiiermic change was 

 still in progress. The assumption that enzyme and hydrolyte 

 become associated, renders possible of explanation a number 

 of otherwise obscure phenomena, for example when formal- 

 dehyde is Condensed under laboratory conditions an inactive 

 mixture of d- and 1-hexose results. „If condensation took place 

 in immediate contact with a compatible enzyme, it is concei- 

 vable that a bias would be given to the synthesis sufficient to 

 determine change whoUy in the one of two possible directions." 

 Yeast which ferments the hydroschists of cane-sugar contains 

 invertase and maltase which .'are respectively compatible with 

 the two hydroschists, If these two enzymes are present as 

 parts of a protoplasmic complex it is easy to understand why 

 yeast should ferment both fructose and glucose. The existance 

 of contiguous maltase and invertase in the protoplasmic complex 

 might determine the formation of glucose and fructose in con- 

 tiguity and these might then unite to form cane-sugar which sub- 

 stance was shown by Brown and Morris to be a primary 

 product of plant metabolism. It may also be supposed that 

 glucose is formed initially as an open chain Compound and 

 that the formation of a y-oxide confers stability on the mole- 

 cule. Starch may be formed by the condensation of a number 

 of Potential glucose molecules prior to closure of the oxide- 

 ring. 



Turning to the albuminoide, if carbohydrates were asso- 

 ciated with the protoplasmic complex they might determine 

 the formation of compatible enzymes, just as enzymes may 

 determine the formation of compatible carbohydrates. 



E. Drabble (London).. 



Berthelot, Recherches sur la dessiccation des plantes 

 et des tissus vegetaux: Periode de fenaison non 

 reversible. — Equilibre final dans des conditions 

 at m osp heriques moyennes. (C. R. de KAcad. des Sc. 

 de Paris. 7 Novembre 1904.) 



Les experiences ont porte sur des plantes vivaces ou 

 annuelles tr^s variees: f^tuque, ble, Mesembryanthemum, Ulex, 

 mousses. 



La loi de dessiccation des differentes plantes examinees 

 est, d'apres la mesure de sa progression, la meme. A chaque 

 instant, eile s'opere sensiblement avec une vitesse proportioneile 

 ä la quantite d'eau restant dans la plante, et eile tend vers 

 une limite approximative, oü il se produit un equilibre. La 

 plante retient ä froid une certaine dose d'eau, ^liminable ä 

 110*^. L'eau retenue ä froid correspond ä un equilibre exprime 

 par des chiffres voisins pour les diverses plantes etudiees. 



Jean Friedel. 



