CHONDRIOSOMES 



83 



The chondriosomes have generally been regarded as essentially com- 

 parable in plants and animals,^ although their behavior may not be the 

 same according to the view of some workers. N. H. Cowdry finds plant 

 and animal chondriosomes to be practically identical in morphology, 

 reaction to fixatives and dyes, and distribution in resting and dividing 

 cells; any conspicuous differences in arrangement seem to be due to the 

 more pronounced polarity of many animal cells. 



Chondriosomes appear in living cytoplasm in the form of minute 

 globules, vesicles, straight or curved rods, smooth threads, chains of 

 granules, nets, and other more irregular bodies (Fig. 43). These forms 



Fig. 43. — Chondriosomes in plant and animal cells. A, nerve cell of guinea pig. 

 (After E. V. Cowdry, 19146.) B, tapetal cell of Nymphwa alba. (After Meves, 1904a.) 

 C, living epidermal cell of tulip petal. D, ascus of Pustularia vesiculosa. E, hypha of 

 Rhizopus nigricans. F, portion of embryo sac of Lilium; chondriosomes clustered about 

 nucleus. G, cell of root tip of Allium. (C-F after Guilliermond, 1918.) 



can be seen to change into one another, especially when the cultural 

 conditions are altered.^ Such changes are in part the result of cyto- 

 plasmic streaming. The same variety of form is encountered in fixed 

 tissues. Particular types tend to predominate in certain tissues. 

 Although it may be convenient at times to designate rods or threads as 

 "chondrioconts" and chains of granules as "chondriomites, " it is to be 

 remembered that the forms assumed by the chondriosomal material are of 

 minor importance. For practically all purposes the now synonymous 

 general terms chondriosomes and mitochondria are sufficient. The total 

 chondriosomal content of the protoplast has been called the chondriome.^ 



3 N. H. Cowdry (1917), Mangenot and Emberger (1920), Bouygues (1924). 



« Lewis and Lewis (1915, 1924), Chambers (1915, 1924), Anitschkow (1923), 

 GuiUiermond (1925a). N. H. Cowdry (1920) finds them to be more stable in Pisum 

 roots. 



* Meves, GuiUiermond. P. A. Dangeard (1924, 1931) uses the terms cytosomes and 

 cytome for these elements in plant cells. For an older and more prevalent use of the 

 term "cytosome," see p. 2. 



