THE LYMPHATIC SYSTEM. 



177 



their origin. These septa are not complete partitions, but consti- 

 tute an open framework, which, in consequence of its radiating 

 arrangement, produces wider spaces in the cortical than in the 

 medullary portion. To this the follicles correspond by being 

 broadest at their peripheral portions. It must not be under- 

 stood that the lymphoid masses, either follicular or cylindri- 

 cal, are closely embraced by the septa ; they are separated from 

 the latter, and from the sheath as well, by spaces, the " invest- 

 ing spaces of the follicular portion" (Frey), or sinuses of tlie 





FIG. 79. Section of the medullary substance of a lymphatic gland from the ox : a, follicular cord ; ft, 

 trabeculae ; c, path pursued by the lymph ; d, blood-vessels. Magnified 300 diameters. Recklinghausen. 



cortical substance (Ranvier), and the lymph-passages (Frey) 

 or cavernous plexus (Ranvier) of the medullary portion. These 

 spaces are maintained by a network of line fibres (tenter-fibres 

 of Frey) derived from the septa, being given off at nearly right 

 angles to the latter. The bundles of fibres composing them 

 divide and reunite, forming meshes, and extend to the follicles 

 and cords. In reality, they do not end here, but are continued 

 to form the reticular tissue of these bodies by dividing into a 

 still finer network, which differs in the different portions only 



