iv.] YEAST. 87 



nitrogenous " animal " substance ; and that such a sub- 

 stance is contained in all ferments. Before him, Fabroni 

 and Fourcroy speak of the " vegeto-animal " matter of 

 yeast. In 1844 Mulder endeavoured to demonstrate 

 that a peculiar substance, which he called " protein," 

 was essentially characteristic of living matter. 

 In 1846, Pay en writes: 



" Enfin, une loi sans exception me semble apparaitre dans les faits 

 nombreux que j'ai observes et conduire a envisager sous un nouveau 

 jour la vie ve"getale ; si je ne m abuse, tout ce que dans les tissus 

 vegetaux la vue directe ou amplifiee nous permet de discerner sous la 

 forme de cellules et de vaisseaux, ne represeute autre chose que les 

 enveloppes protectrices, les reservoirs et les conduits, a 1'aide desquels 

 les corps animes qui les secretent et les fagonnent, se logent, 

 puisent et charrient leurs alimeuts, deposent et isolent les matieres 

 excretees." 



And again : 



" Afin de completer aujourd'hui l'e*nonce du fait ge"ne"ral, je rappel- 

 lerai que les corps, doue" des fonctions accomplies dans les tissus des 

 plantes, sont formes des elements qui constituent, en proportion peu 

 variable, les organismes animaux; qu'ainsi Ton est conduit a reconnaitre 

 une immense unite de composition e"lemeutaire dans tous les corps 

 vivants de la nature." 1 



In the year (1846) in which these remarkable passages 

 were published, the eminent German botanist, Von Mohl, 

 invented the word " protoplasm/' as a name for one por- 

 tion of those nitrogenous contents of the cells of living 

 plants, the close chemical resemblance of which to the 

 essential constituents of living animals is so strongly 

 indicated by Payen. And through the twenty-five years 

 that have passed, since the matter of life was first called 

 protoplasm, a host of investigators, among whom Cohn, 

 Max Schulze, and Klihne must be named as leaders, have 

 accumulated evidence, morphological, physiological, and 



1 "Mem. sur les De"veloppements des Ve"ge"taux," &c. " Mem. Pre"sent6es." 

 ix. 1846. 



