Chapter VII 



63 — 



The Ghondriome 



somes are permanent elements which are found in all parts of the 

 fungi and which are never seen to arise de novo, even in prolonged 

 examination of living material. In addition, the presence of nu- 

 merous division figures of chondriosomes and the regular distribu- 

 tion of these elements among the zoospores seem to indicate clearly 

 that the chondriosomes are transmitted by division from cell to 

 cell and never arise de novo. Proof of this, however, is difficult to 

 furnish, but we shall see later that certain indirect arguments 

 drawn from the study of plastids in chlorophyll-bearing plants seem 

 favorable to the opinion that chondriosomes maintain their indi- 

 viduality in the course of development. 



Research on the development of chondriosomes, carried out by 

 direct observation as well as by mitochondrial techniques, has not 

 furnished any information as to the role of these elements and has 

 not brought any concrete facts to bear on their participation in the 

 secretory phenomena so of- 

 ten attributed to them in 

 animal cytology. 



It is true, as has been 

 seen, that in the asci of 

 Pustularia vesiculosa and of 

 Ascoidea rubescens and in 

 the basidia of the Agarica- 

 ceae the chondrioconts form 

 on their long axes vesicular 

 swellings which have the 

 same appearance as those 

 brought about by the forma- 

 tion of starch grains in the 

 leucoplasts of the phanero- 

 gams. This has also been 

 observed by Lewitsky dur- 

 ing the formation of the 

 oogonium in the Peronosporaceae and more recently by PoissoN 

 and Mangenot in Vampyrella Closterii during the period of diges- 

 tion. It was first supposed, by analogy with the ideas accepted in 

 animal cytology, that these vesicles, appearing when the reserve 

 products are elaborated in the basidium and ascus and then dis- 

 appearing during mitosis, might bear some relation to the forma- 

 tion of these reserve products. But it has been shown by observa- 

 tion of living material that none of these reserve products of the 

 ascus, metachromatin, fats, glycogen, arises in these vesicles. Meta- 

 chromatin is formed in the vacuoles (P. A. Dangeard, Guillier- 

 MOND). Lipide granules always arise in the cytoplasm apart from 

 the chondriosomes, as our observations have allowed us to show in 

 fungi, such as the Saprolegniaceae and Endoynyces Magnusii (Figs. 

 30, 31), where the chondriosomes are very clearly seen in living 

 form. Glycogen also appears in the cytoplasm, as we have been able 

 to establish by direct observation of various fungi treated with 

 iodine-potassium iodide reagent. This reserve product is found 



Fig. 29. — Portions of filaments of Saprolcgnia 

 observed with the ultramicroscope showing (1) only 

 the lipide granules (Gl) illuminated, (2) the chon- 

 driosomes (C) also and (3) the coagulated proto- 

 plasm. 



