88 INTRODUCTION TO CYTOLOGY 



of fibrils of certain types, they do not actually transform into them. 

 Probably the clearest case of the formation of a definite structure by 

 chondriosomes in animal cells is furnished by the nebenkern, which is a 

 chondriosomal body developing into an important constituent of the tail 

 sheath of the spermatozoon (p. 219). 



The observations of several investigators have suggested a connection 

 between chondriosomes and the formation of secretion and storage 

 products. In the pancreas, for example, it was thought^'^ that chon- 

 driosomes become zymogen granules, but Regaud (1911), who with Meves 

 first emphasized the secretory theory in general, thought it more probable 

 that the chondriosomes in some way synthesized the zymogen from 

 materials selected from the cytoplasm (the ''electosome theory"). 

 Reference has already been made to the newer view that chondriosomes 

 furnish a material for the synthesis of secretions in the Golgi region of 

 gland cells (see p. 77). The development of the secretion product in 

 glandular hairs of Salvia has been associated with chondriosomes. ^^ 

 Chondriosomes have also been assigned a role in the elaboration of certain 

 types of yolk in developing eggs^^ and of fat in liver cells. ^^ 



The theory that chondriosomes are in any sense protoplasmic organs 

 with special roles in differentiation and secretion was strongly opposed 

 by A. Meyer (1911, 1920), who contended that they are simply ergastic 

 accumulations of an albuminous nature. Their ergastic nature, according 

 to Meyer, is indicated by the fact that their distribution and behavior 

 are just what would be expected of reserve substances necessary as sources 

 of building material and energy (in meristematic cells, eggs, regenerating 

 tissues, muscles, etc.). They do not transform into differentiations such 

 as myofibrils, but they may lie near them and possibly furnish materials 

 or energy for their upbuilding by the cytoplasm. They do not elaborate 

 or secrete ergastic substances but are themselves such 'substances in 

 process of formation by the cytoplasm. The general view that chondrio- 

 somes are products of metabolic activity rather than distinct proto- 

 plasmic organs has been held in one form or another by many workers 

 and appears to be well supported by many observations on both living 

 and fixed cells. 



The almost universal occurrence of chondriosomes in protoplasm 

 suggests a connection with some fundamental process common to all 

 living matter. That this process may be oxidation, the chondriosomes 

 being a "structural expression of the reducing substances concerned in 

 cellular respiration," was suggested by Kingsbury (1912), who pointed 



21 Hoven (19106), G. Arnold (1912). 



22 Jaretzky and Triebel (1932). 



23Loyez (1909), Dubreuil (1913), Van Durme (1914), Shaffer (1920), Gatenby and 

 Woodger (1920), L. Harvey (1925), Konopacki (1927), Bhatia and Nath (1931). 

 See Wilson (1925, p. 341). 



2" D. Smith (1931), Kater and Smith (1932). 



