Chapter IX 



89 — Chondriosomes & Plastids 



tions, but without, however, bringing forth the slightest histochem- 

 ical proof in favor of this idea. Later (1921) he seems to have 

 abandoned his opinion. He states that chondriosomes can not 

 always be distinguished from plastids in meristematic cells of 

 plants and seems to admit that the chondriosomes are plastids 

 whose functions are multiple, the plastids of chlorophyll-bearing 

 plants being only a special variety. 





•• 



• ••• 



• • •«, 



/.••%.• 



• •• • 







m 



Fig. 57. — Chondriosomes and plastids in leaf cells of Elodea 

 canadensis, I, in embryonic cells, II, at the beginning of differentiation. 

 o, the chondriome; b, plastids and c, chondriosomes drawn separately. 

 Ill, later stage, o, plastids; b, chondriosomes. 



. On the basis of research carried out exclusively in the phanero- 

 gams, Meves (1918) expressed a theory which is the exact opposite 

 of that held by most of the authors just discussed. This eminent 

 cytologist observed that, in the meristem of buds, mitochondrial 

 technique brings out both chondrioconts and granules, and that all 

 the chondrioconts are transformed into chloroplasts in mature cells. 



