BLOODVESSELS OF THE ORAL CAVITY. 



587 



which are at the same time somewhat less numerous. As a 

 general rule the arterial and venous trunks pursue a parallel 

 course. 



The veins arising from the plexus each run by the side of 

 an artery into the submucous tissue, where, having collected 

 together and freely anastomosing with each other, they form a 

 wide-meshed plexus similar to and parallel with that formed 

 by the arteries. These relations are met with throughout the 

 whole extent of the oral cavity, except only that the closeness 

 of the plexus presents considerable variation at different parts, 

 in accordance with the greater or less development of the 

 capillaries of the papillae. 



As a general rule, it may be stated that the larger the pa- 

 pillae, the more extensive is the capillary plexus in their 

 interior. 



At the margins of the lips, where the largest papillae are 

 found, from three to five branches of the terminal arterial 

 plexus enter each papilla, and by their divisions and anasto- 



Fiff. 112. 



Fig. 112. PapillaB of the lip. 



moses form an elongated but wide-meshed capillary plexus 

 (fig. 112). The transition into the venous channels takes place 

 by one or more capillary loops usually situated at the apex of 



s s 



