No. 3.] STUDIES ON THE HETERONEMERTINI. 393 



nutritive substances which the cell has taken up from without, 

 since they are never found within the nucleus. ^ I conclude 

 that the chromophilic corpuscles are metamorphosed portions of 

 the cytoplasm produced by a dense welding together of the 

 microsomes of the latter at different points in the cell body; 

 this would account for their power to stain deeply, and their 

 homogeneous appearance. Again, some stain scarcely more 

 deeply than the surrounding cytoplasm, and their bounding 

 membranes are scarcely appreciable, while others stain intensely, 

 and are provided with relatively thick limiting membranes; and 

 all intergradations between these two stages occur. These 

 facts are sufficient to show that the chromophilic corpuscles of 

 Lineiis are differentiated portions of the cytoplasm of the cell, 

 the process of differentiation consisting in a compression or 

 fusing together of the primitive microsomes. Analogical meta- 

 bolic cytoplasmic changes are found, e.g., in the formation of 

 yolk particles in the egg cell of Stic/iosiem^na (Montgomery, 



'95). 



Corpuscles, somewhat similar to these, I find described by 

 Dehler ('95) for the sympathetic ganglion cells of the frog : 

 "Diese Schollen . . . haben eine ziemlich unregelmassige Ge- 

 stalt : von einer kornchenartigen Zusammensetzung an findet 

 man sie bis zur Gestalt von flachen Dreiecken mit breiter Basis ; 

 auch grosse Schollen, die aus kleineren lose zusammengesetzt 

 erscheinen, sind vorhanden; sie sind nicht kugelig und haben 

 niemals scharfe Ecken, so dass der Ausdruck "Scholia" der 

 einzig passende zu sein scheint. . . . Manchmal finden sich in 

 kleineren Zellen wenig oder keine chromatischen Schollen; 

 dafur ist dann die Zelle diffus und intensiver gefarbt. Flesch 

 nennt dieses Verhalten Chromophilic. Ich erklare mir das so, 

 dass in solchen Fallen die chromatische Substanz nicht wie zu 

 Schollen geronnen, sondern diffus in die achromatische Sub- 

 stanz verteilt ist; wahrscheinlich ist sie in den kleineren Zellen 

 in derselben oder fast derselben Menge vorhanden, nur gleich- 

 massiger verteilt wie in den grossen." Dehler finds these 

 "Schollen," which differ from the corpuscles of Linens in their 



1 Cf. Korschelt's studies, " Zur Morphologie des Zellkernes," and the obser- 

 vations of mine upon nutritive processes in mesenchym cells ('97). 



