278 



ABSOKPTION LYMPH AND CHYLE. 



or more, returning to their original size as soon as the distending fluid is 



removed. 



In the lymphatics of the skin, the only important peculiarity which has 



not yet been mentioned is 

 that the vessels appear to 

 be very unequally distrib- 

 uted in different parts of 

 the surface. According to 

 Sappey, they are particularly 

 abundant in the scalp over 

 the biparietal suture, the 

 soles of the feet and the 

 palms of the hand, the fin- 

 gers at the lateral portion of 

 the last phalanges, and the 

 scrotum. In the median 

 portion of the scrotum they 

 attain their highest degree 

 of development. They are 

 also found, though in less 

 number, originating from 

 around the median line on 

 the anterior and posterior 

 surface of the trunk, the 

 posterior median portion of 

 the extremities, the skin 

 over the mammae, and around 

 the orifices of the mucous 

 passages. Sappey has in- 

 jected lymphatic vessels in 

 the anterior portion of the 

 forearm, the thigh and the 

 leg, and in the middle por- 



tion of the face > altho g h 



they are demonstrated with 

 difficulty in these situations. If they exist at all in other portions of the cu- 

 taneous surface, they are not abundant. 



In the mucous membranes the lymphatics are very abundant. Here are 

 found, as in the skin, two distinct layers which enclose between them the 

 entire thickness of the mucous membrane. The more superficial of these 

 layers is composed of a rich plexus of small vessels, and beneath the mucous 

 membrane, is a plexus consisting of vessels of larger size. The superficial 

 plexus is very rich in the mixed structure which forms the lips and the glans 

 penis, and around the orifices of the mouth, the nares, the vagina and the 

 anus. There are certain mucous membranes in which the lymphatics have 

 never been injected. In the serous membranes, lymphatics have been demon- 



FIG. 87. Superficial lymphatics 

 of the arm (Sappey). 



