LYMPHATIC ORGANS 175 



works. Some of the arteries, instead of passing directly to the lym- 

 phatic tissue, follow the septa, supplying these and the capsule, and 

 also sending branches to the surrounding lymphatic tissue. A few 

 small vessels enter the capsule along the convexity of the organ and 

 are distributed to the capsule and to the larger septa. 



Lymphatics. — The afferent lymph vessels enter the node on its 

 convex surface opposite the hilum, penetrate the capsule, and pour 

 their lymph into the cortical sinuses. The lymph passes through the 

 sinuses of both cortex and medulla, and is collected by the efferent 



Afferent „.,i,;V;%/ /r^% {. .'.^i.^, /, 

 yrmph. ves. '^(p:^.. ^l i . ;..V^" 



Fig. lor.- — ^From a Section through the Axilla of a Human Embryo of 125 mm. 

 (4-5 months), showing an Early Stage of a Lymph Gland. (Kling.) 



lymph vessels which leave the organ at the hilum. Within the node 

 the lymph comes in contact with the superficial cells of the nodules 

 and of the lymph cords. These cells are constantly passing out into 

 the lymph stream so that the lymph leaves the node much richer in 

 cellular elements. 



Nerves are not abundant. Both medullated and non-medullated 

 fibres occur. Their exact modes of termination are not know^n. 



!i Lymph.^ — This is a colorless fluid containing rather few formed 

 ements in the w^ay of w^hite blood cells, blood platelets, granules 

 and fat. Most of the cells are of the small lymphocyte type although 

 some large lymphocytes and polymorphonuclear leucocytes are 

 found. In the lymph of the intestinal mucosa, especially during 

 digestion, fat droplets are present in large numbers giving the fluid a 

 milky appearance. This is known as chyleh 



