INTERSTITIAL CELLS OF TESTICLE IN DIDELPHYS. 189 



this substance be formed by the coalescence of the chondriosomes, 

 nor that the elimination be accompanied by a partial destruction 

 of the cell. 



While the existence of these strangely deformed chondriosomes 

 is perhaps not very interesting in itself, it calls the attention of 

 the cytologist to the possibility of a confusion between different 

 cellular structures. Regardless of whether or not my interpreta- 

 tion be correct, two things are evident: (i) That the network has 

 nothing whatever to do with the apparatus of Golgi, as is shown 

 after the application of Ramon y Cajal's method; (2) that it 

 bears a remarkable resemblance to many of the structures de- 

 scribed as the apparatus of Golgi. There is one instance in the 

 literature in which the chondriosomes, after application of a 

 silver method, have been mistaken for the Golgi's apparatus 

 (the cartilage cell, by Pensa, 1901 )/ and it is possible that a 

 similar error is also the basis for Monti's interpretation of this 

 structure in the adult nerve-cell. According to that writer 

 (1915), what was described in these cells as the apparatus of 

 'Golgi is identical with the chondriosomes. I have discussed her 

 paper extensively in another place (1919). Having since dis- 

 covered this network in the interstitial cells of the opossum I am 

 inclined to believe that Monti has been misled by a similar 

 appearance. 



Another point which I feel should be touched upon in this 

 connection is Holmgren's trophospongium theory. In its latest 

 form this theory claims the existence in a tissue of two types of 

 cells the parenchymal cells and the trophocytes. The former 

 are penetrated by processes of the trophocytes, processes which 

 form the trophospongial net and become, under certain circum- 

 stances liquified, forming the " Kandlchen des Trophospongiums." 

 The role of the trophocytes is, as their name implies, a trophic one. 

 While Holmgren himself has never published anything on the 

 interstitial cells of the testicle, these are the only objects for 

 which his theory has found whole-hearted support. In one 

 paper Bouin and Ancel (1905, i) describe, in the first generation 

 of interstitial cells in the testicle of horse fetuses from 22 to 42 

 cm. long, a structure which is "I'homologue du trophosponge de 



1 Pensa himself later on (1913) acknowledged his mistake. 



