Guilliermond - Atkinson — 122 — Cytoplasm 



of small closed sacs, automatically forming and maintaining them- 

 selves at the same time that they produce all the physico-chemical 

 transformations taking place in the cell. This establishes the 

 bond, heretofore mysterious, between cellular structure and vital 

 activity." 



COWDRY and Lecomte du Nouy have shown, moreover, by 

 meticulous measurements, that the surface of the chondriosomes is 

 greater than that of the nucleus, although the total nuclear volume 

 is about five times greater than the total chondriosomal volume of 

 the same cell. The mitochondrial substance seems therefore to 

 realize a maximum surface with the minimum of material and 

 these investigators think that on these interfaces of considerable 

 area, certain substances may accumulate and the concentrations 

 attained may allow pluri-molecular reactions of the very highest 

 importance to take place between the interfaces. 



Robertson has formulated a theoiy similar to that of Devaux 

 based on the data brought out by Marston who showed that dyes 

 of the azine series, such as Janus green, have a precipitating 

 action specific for proteases and that, moreover, the action of these 

 enzymes is doubled in the presence of an emulsion of lecithin, the 

 surface of the lecithin serving as the catalytic surface. Robertson 

 thinks, therefore, that the staining of the chondriosomes by Janus 

 green is an index of the presence of proteases in their substratum 

 and that the chondriosomes enclose proteases of reversible action, 

 capable of bringing about both the synthesis and the hydrolysis of 

 proteins. He believes that the chondriosomes may be the site of 

 proteosynthesis, a synthesis which takes place by virtue of the 

 lipide surface of the chondriosome which acts as the catalytic 

 surface. In the course of his research on the vacuolar system of 

 animal cells, Parat noticed that the cytoplasm and the chondrio- 

 somes seem to have a reducing power, while the vacuoles seem to 

 have an oxidizing power. This investigator is thus led to formu- 

 late the hypothesis that the chondriome brings about oxidation- 

 reductions by means of which cellular synthesis is carried out, and 

 that the second phase, or respiratory oxidation, which follows 

 these phenomena occurs in the vacuoles. Having observed, more- 

 over, that the chondriosomes and the vacuoles are often in intimate 

 contact, Parat supposes that the combination, chondriome + vac- 

 uome, is responsible for protein synthesis which, according to 

 Robertson, entails a lipide phase and an aqueous phase. This 

 author thinks, also, that the vacuolar system may be the region in 

 which operations begun in the chondriome are completed. Re- 

 cently Miss Le Breton, basing her ideas on those of Robertson 

 and Marston, and on investigations of Joyet-Lavergne, Giroud, 

 and Parat, sought to show that chondriosomes are found in the 

 conditions necessary and sufficient for them to be the center of 

 protein synthesis. 



Recent work (Guilliermond and Gautheret) does not con- 

 firm Parat's hypothesis. The fact that chondriosomes stained 

 vitally with Janus green lose their color rather quickly, a fact 



