Guilliermond - Atkinson 



— 60 — 



Cytoplasm 



conts. The chondrioconts become thinner and thinner as they 

 elongate which seems to indicate that they are formed by a pro- 

 gressive stretching of the mitochondria. In the young zoosporan- 

 gia, the chondriosomes are all in the state of mitochondria which 

 subsequently, together with the cytoplasm, assemble about each of 

 the numerous nuclei, thus outlining the circumferences of the fu- 

 ture zoospores which are seen as separated by hyaline areas. All 

 the zoospores when mature enclose a chondriome made up exclu- 

 sively of mitochondria which, at the time of germination, are trans- 

 formed in the germinating tube into chondrioconts. 



The development of the chondriosomes is also very well known 







•J?*, 



\ • 



"vs^i 







«iP 









^w,.; 





■'■■\Zy D 



-A-ii 



Fig. 24 (left). — The chondriome in Myxomycetes and the Plasmodiophoraceae. A, frag- 

 ment of the Plasmodium of Physarum (original) ; B, spores of Fuligo septica (after Lewitsky) ; 

 C, spores of Hemitrichia vesparum (after Cowdry) ; D, spores and zoospores of Fuligo septica 

 (after Vonwiller) ; E, young Plasmodia of Plasmodiophora Brassicae (after Milovidov). 



Fig. 25 (right). — Allomyces arbiisculus. 1, elongated chondrioconts in the vegetative fila- 

 ment. 2, 3, the chondrioconts grouped about the nuclei in the gametangium. 4, mitochondria 

 surrounding the spores as they are cut out. C, chondrioconts; L.G., lipide granules colored 

 brown with osmic acid; N, nucleus. Champy-KuU method. (After Hatch). 



in the ascus of Pustularia vesiculosa. It was here that they were 

 studied for the first time in the fungi by us and then by JANSSENS 

 and Helsmortel. They present a series of interesting phenomena. 

 All of the ascogenous hyphae, those from which the asci will be 

 formed, show a chondriome made up of numerous chondrioconts 

 densely clustered about each nucleus. It is known that the ascus 

 forms at the terminal portion of these hyphae. This terminal, 

 recurved, crosier-like portion is occupied by a binucleate cell whose 

 two nuclei divide simultaneously. Then two transverse walls form, 

 marking off three cells, of which the middle one, that occupying the 

 arch of the crosier, encloses two nuclei whereas the others, that at 

 the extreme tip and that at the base, contain only a single nucleus. 

 The middle binucleate cell destined to form the ascus, contains at 

 first, around each of its two nuclei, a small mass made up of the 



