Chap. xii.] SIMPLE LYMPHATIC GLANDS. 



97 



nucleated protoplasmic cells, which are the concentric 

 bodies of Hassall (Fig. 5 OB). They are met with al- 



Fig-. 59A. Section through the Thymus Gland of a Foetus. 



a, Fibrous tissue between the follicles ; b, the cortical portion of the follicles ; 

 c, the medullary portion. 



ready in the early stages of the life of the thymus, and 

 cannot therefore be connected with the involution of 

 the gland, as maintained by Afanassief, according to 

 whom the concentric cor- 

 puscles are formed in 

 blood-vessels which there- 

 by become obliterated. 

 According to Watney 

 they are concerned in the 

 formation of blood- vessels 

 and connective tissue. 



The lymphatics of the 

 interfollicular septa and 



Fig. 59B. Two Concentric or Has- 

 sall's Corpuscles of the Tbymus. 

 Foetal Gland. 



trabeculse always contain 



numbers of lymph corpuscles. The blood capillaries 

 of the follicles are more richly distributed in the 



