ABSORPTION. 217 



through the gland. The lymph sinus is crossed by a network of 

 retiform connective tissue which offers considerable resistance to 

 the passage of the lymph. The gland substance consists also of a 

 framework of retiform connective tissue in the meshes of which large 

 numbers of lymph-corpuscles are contained. The gland substance 

 is separated from the lymph sinus by a dense layer of a reticulum, 

 which, however, does not prevent lymph and even corpuscles from 

 passing through it into the lymph sinus. 



The lymph-glands are abundantly supplied with blood-vessels. 

 The arteries enter the gland at the hilum, penetrate into the medullary 

 substance, and terminate in a fine capillary plexus which is supported 

 by the connective tissue. The veins arising from this plexus leave 

 the gland also at the hilum. 



tr. 



FIG. go. DIAGRAMMATIC SECTION OF A LYMPH-GLAND, a. L, Afferent, e. /., efferent 

 lymphatics. C. Cortical substance. M. Reticular cords of medulla. /. 5. Lymph 

 sinus, c. Capsule, with trabeculae, tr. (Landois and Stirling.') 



The lymph-vessels which enter a gland first ramify in the in- 

 vesting membrane and then open directly into the lymph sinus. 

 The vessels which leave the gland are also in communication with 

 the sinus. After the lymphatics enter the gland they lose their 

 external and middle coats, retaining only the internal or endothelial 

 coat, which lines the inner surface of the lymph sinus. The current 

 of lymph, therefore, is from the afferent vessels through the lymph 

 sinus into the efferent vessels. In addition to this primary current, 

 there is a secondary current flowing from the capillary blood-vessels 

 outward and into the sinus, which carries with it large numbers of 

 lymph-corpuscles. It is quite probable that the movement of the 



