GOLGI APPARATUS IN STRIATED MUSCLE. 



paper is illustrated by a remarkable series of figures. Veratti 

 found, in essential agreement with Cajal and Fusari, that there 

 is present in the striated muscle fiber an elaborate system of 

 very delicate fibers, which form an anastomosing network rather 

 easily blackened in a specific manner by the so-called black 

 reaction (reazione nera) of Golgi. This network consists prima- 

 rily of a series of regularly arranged cross-fibers, located in 

 various but definite planes as determined by the phenomena of 

 cross-striation in the muscle fiber itself. These cross-threads 

 are connected by more irregularly arranged fibers running 

 parallel to the muscle columns. This whole network has been 

 shown with reasonable certainty to occupy the interstices between 

 the muscle fibrils, lying thus in the sarcoplasm but having an 

 entirely independent existence. The general accuracy of these 

 findings has subsequently been substantiated by Martinotti ('04), 

 Sanchez ('07) and particularly Holmgren ('08). 



It was shown, furthermore, especially by Veratti that the 

 regular arrangement of the network is gradually arrived at by 

 progressive differentiation of a netw r ork which is much less 

 regularly arranged in the embryo, for example of mammals. 

 Martinotti ('04) was able also to show that a return to a more or 

 less embryonic condition of the network could be effected in the 

 rabbit by starvation, or section of the fibers of the nerve supply. 

 But in this direction Veratti went still further by demonstrating 

 that the condition of the network at birth varies in different 

 mammals. Thus in the mouse and rabbit, the final arrangement 

 of the net is not achieved until some days after birth ; while in 

 the guinea-pig, the final (adult) condition is present at birth, 

 and an arrangement comparable to that of the mouse at term, 

 can be found only in the guinea-pig fetus about fifteen days 

 before birth. In this connection also it is of interest to note 

 that the results for instance of M. Sanchez ('16) on the Purkinje 

 cells of rabbits, show that the Golgi apparatus in these cells 

 only attains its adult development and arrangement by a gradual 



most American workers, but a general idea of the results can be found in Cajal 

 ('90) and Fusari ('94). It may also be noted here that the relation of the Cajal- 

 Fusari network revealed by silver nitrate, to the network in striated muscle stained 

 by gold chloride, is still a matter of doubt. In these notes, the latter network will 

 not be considered. 



