194 



Studies oi" tliu Interstitial Cells of Lejdig 



3. This variety is similar to the preceding, but is characterized by the 

 presence of large acidophile granules, which have about the same size 

 as those noted in the germinal epithelium of the early embryo. They are 

 more granular in appearance, however, than the latter, and in prepara- 

 tions stained by Mallory's method they take the acid fuchsin, whereas 

 the granules of the epithelium are stained by the aniline blue. With 

 Mann's mixture of methyl blue and eosin they are stained by eosin. Al- 

 though acidophile, they do not stain with as much intensity as the 

 granules of eosinophile leucocytes. The granules are situated, for the 

 most part, in the peripheral portion of the cytoplasm; occasionally a 

 cell is found which seems loaded with them throughout, but, as a 

 general rule, they are largest and most numerous near the periphery. No 

 such granules were seen within the seminal tubules; in the spaces be- 

 tween the Leydig's cells, however, small collections of them were rather 

 frequently encountered, which in most cases were undoubtedly small por- 



FlG. 



Fig. 



Fig. 1. Fig. 2. 



Types of Leydig's cells in pig one month old. x SOO. 



Pig three months old. A small group of Leydig's cells. x 800. 



tions sectioned from the periphery of granule-bearing cells, but in some 

 instances seemed to be free. All the cells of these three varieties have 

 rather coarse, well defined cell-boundaries, especially marked in the case 

 of the vacuolated cells. These boundaries frequently stain differently 

 from the cytoplasm proper; in preparations stained by Mann's solution 

 of methyl blue and eosin the cell-boundaries quite commonly are blue, 

 while the cytoplasm takes the eosin. Many of the cells have two nuclei, 

 but no mitotic figures were observed. A review of my preparations 

 of the testis from the embryo just before term shows that all these varie- 

 ties of cells are present there; indeed the principal difference between 

 the two glands, so far as Leydig's cells are concerned, is the atrophy of the 

 subalbugineal layer in the pig one month old. The granules, however, 



