THE THYMUS GLAND, 167 



seems to be formed, in part at least, by a transforma- 

 tion of the contents of the epithelial cells, and its 

 formation under pathological conditions gives rise 

 to one of the forms of goitre. 



TECHNIQUE. 



The thyroid of a child or adult better the former 

 is cut into small pieces and hardened in Miiller's fluid. 

 Sections are stained double and mounted in glycerin or 

 balsam. 



THE THYMUS GLAND. 



The thymus gland is composed of numerous 

 lobules bound together by loose connective tissue, 

 the entire gland being enclosed by a connective- 

 tissue envelope. The lobules are irregular in shape, 

 and are surrounded by a connective-tissue capsule. 

 This capsule sends inward numerous trabeculce, which 

 divide the cortical portion into irregular chambers. 

 These chambers are filled with the follicles of the 

 lobule. These follicles have a supporting frame- 

 work of delicate reticulum, the meshes of which are 

 filled with lymphoid cells. As the follicles approach 

 the medullary portion they become fused with one 

 another. The medullary portion of the follicle has a 

 large meshed reticular framework, which is more 

 sparingly filled with lymphoid cells, and has a more 

 transparent appearance than the follicles of the cor- 

 tex. Scattered through the medulla, in varying 



