320 THE ADRENAL, GENERAL MOTOR, AND VAGAL SYSTEMS. 



ginning from the inner portion of the organ. A fine net- 

 work of capillary blood-vessels which acts as a supporting 

 fabric, furnished by underlying arterioles, is the central feat- 

 ure; this, in turn, is surrounded with a close net-work of 

 fibrils, in which "lymph-corpuscles, small round cells, with a 

 large nucleus and very little perinuclear protoplasm" so com- 

 pletely preponderate as to almost entirely obscure the net- 

 work. 7 But there is a feature of special interest here which 

 will remind us of the cell-forming membrane of Kolliker found 

 in villi: i.e., a central nodule, described by Flemming, in which 

 some cells undergo active karyokinetic division, while others, 

 lymphocytes, are formed in continuous quantities. "In the 

 center of the nodule," say Bohm and von Davidoff, 8 "the cells 

 often show numerous mitoses, and it is here that an active 

 proliferation of the cells takes place. The cells may either 

 remain in the lymph-follicle or the newly-formed cells are 

 pushed to the periphery of the nodule and are then swept into 

 the circulation by the slow lymph-current which circulates be- 

 tween the wide meshes of the reticular connective tissue." The 

 third portion is the interval referred to, a delicately partitioned 

 sinus which surrounds the follicle. To this sinus the lymph, 

 originally from the blood-capillaries, after it has permeated 

 the meshes and cell-spaces of the adenoid tissue and became 

 charged with the newly created cells, gravitates, to finally find 

 its way into the lymph-vessels of the submucous tissues be- 

 neath. 



The physiological functions of the follicle seem plain when 

 we consider two salient features of its anatomical relations 

 with the mucous surface of the intestine and with the villi. 

 As to the relationship between the interior of the follicle and 

 the intestinal canal, it is suggested by the perforations to which 

 we have previously referred, but there seems to be no mech- 

 anism to insure absorption. The case is not the same, however, 

 in respect to the connection with the villi. Indeed, the lym- 

 phatic vessels which originate from the lacteals of the latter 

 constitute the afferent supply of the sinus, while the lymphatic 

 vessels of the submucous tissue represent its efferent system. 



*Clarkson: "Histology," 1896. 



8 Bohm and von Davidoff: Loo. cit. 



