

LYMPHATICS AND NERVES OF THE ADRENALS. 121 



occurrence. The diverse structure presented by the cortex renders a 

 certain variation in the mode of division of the vessels probable. 



The vessels of the medulla are derived from the capillaries 

 of the innermost layer of the cortex. They form a narrow- 

 meshed plexus of vessels varying in their width, often pre- 

 senting considerable dilatations, and discharging their contents 

 into the renal veins. The central portion of the medulla, 

 according to Arnold, is fed by the arteries running in the 

 connective-tissue trabeculae, which communicate with the 

 medullary capillaries. 



Both the narrower cortical and the wider medullary capil- 

 laries are very thin- walled ; their parietes being composed only 

 of an endothelial tube. They lie in contact with the paren- 

 chymatous bodies, and are so firmly united with the sparingly 

 intervening stroma as to be isolated with difficulty. This 

 circumstance has led to the belief that there are here blood- 

 paths destitute of walls. 



LYMPHATICS. In addition to the few superficial lymphatics 

 described by Ecker, Kolliker, and Arnold, the last-named author 

 describes a deep set. We may also regard the irregularly 

 dilated thin-walled cavities observed by Moers within the 

 gland accompanying the arteries, to be sections of lymphatic 

 canals. 



NERVES. The adrenals are rich in nerves ; the supply being 

 derived from the ganglion semilunare, the plexus renalis, and 

 from the phrenic and pneumo-gastric nerves. The branches 

 enter the organ by its internal and lower border, and divide, 

 for the most part, in the medullary substance, where they form 

 large decussating cords, and more rarely delicate plexuses. 

 Bi- and multi-polar ganglia are frequently observable, partly 

 isolated, partly forming large groups in the nerves of the 

 medulla, at their points of division (Holm and Eberth). Gan- 

 glionic cells are seldom found in the cortex. The nerves are 

 composed of fine dark-edged fibres. 



It is still doubtful whether the nerves terminate in the interior of 

 e organ, or only traverse it in the form of an endless plexus. 



