Chapter XI — 123 — Role of Chondriosomes 



observed by many authors (Guilliermond, Parat, Sorokin) had 

 led to the acceptance of the idea that chondriosomes have the power 

 to reduce Janus green to its leucoderivative. It will be seen that 

 this interpretation is inexact and that the chondriosomes are in- 

 capable of carrying out this reduction. All that they do is to 

 reduce Janus green to its rose derivative, which, having less affinity 

 for the chondriosomes than for the cytoplasm or the vacuole, dif- 

 fuses into these latter. The chondriosomes, moreover, share this 

 property with the vacuole when the latter contains substances 

 capable of holding the dye and often the reduction even begins in 

 the vacuoles and is completed in the chondriosomes. On the whole, 

 Janus green is reduced wherever it is localized and the chondrio- 

 somes do not seem to have a more active role in this reduction than 

 the other elements of the cell. The chondriosomes can not then 

 be considered as having a reducing capacity and the vacuoles as 

 having an oxidizing capacity. 



Nothing is positively known about the role of the chondrio- 

 somes. One fact, however, stands out from recent research. This 

 is that the chondriosomes, like the leucoplasts, have the property 

 of being stained selectively and in a transitory manner by a rather 

 large number of vital dyes, which dyes later accumulate in the 

 vacuole. It could therefore be supposed that they behave in the 

 same way in the absorption of various substances which the cell 

 takes from the external medium. According to this theory, these 

 substances are taken up by the chondriosomes, then thrown off 

 into the vacuole, either directly, or after having undergone some 

 transformation (synthesis), this transformation being brought 

 about during contact with the chondriosomes, by the mechanism 

 suggested by Devaux. This hypothesis, which seems to agree both 

 with that of Regaud and that of Devaux, explains the accumula- 

 tion of protein by the chondriosomes of the liver when an animal 

 is subjected to an exclusively nitrogenous diet (R. Noel) and 

 explains the capacity of leucoplasts to take up amino acids 



(VOLKONSKY). 



Apart from these hypotheses, it has been thought, also, that 

 the chondriosomes and the plastids might have a role in the phe- 

 nomena of heredity. This was the opinion of Meves. From work 

 carried out on plants with variegated leaves and branches, that is 

 to say plants presenting a mosaic of green leaves and colorless 

 parts lacking chlorophyll, various authors suggested a role that the 

 plastids seem to have in heredity. Thus, to cite only one example, 

 a variegated hybrid of Oenothera (O. rubridivaricata) , can form 

 flowers at the extremity of green branches and at the ends of 

 colorless branches. Now, after pollinating the flowers on the un- 

 colored branches by the pollen of flowers on uncolored branches, 

 Renner obtained entirely colorless seedlings. The pollination of 

 flowers of uncolored branches by pollen from flowers on green 

 branches has given a mixture of colorless seedlings, variegated 

 seedlings and normal green seedlings. In a second series of ex- 

 periments, Renner pollinated flowers from green branches by 



