TUMORS. 



333 



vascular tumors. These are, however, not true angiomata, although 

 sometimes reckoned among them, and in many cases closely allied to 

 them. Such are the so-called arterial varix, or cirsoid aneurisms, and 



FIG. 179. ANGIOMA TELANGIECTOIDES FROM THE SKIN. 

 This section is from a vascular naevus, "strawberry mark," of the skin. 



haemorrhoids, and various lymphectasiae. True augiomata are of two 

 kinds I. Ha?mangioma, and II. Lymphaugioma. 



1. Hsemangioma. These tumors are of two types: 1. Those formed 

 largely of capillary blood-vessels with either thin or thickened walls, 

 embedded in a more or less abundant connective-tissue stroma. These 

 are called simple angiomata or angioma telangiectoides (Fig. 179). The 

 walls of the vessels in these 



tumors are frequently dilated 

 or pouched, and usually form 

 a tangle of curled and inter- 

 twined vessels. They occur 

 most frequently in the skin 

 or subcutaneous tissues, usu- 

 ally about the face, and may 

 project above the general sur- 

 face or be on a level with it. 

 Such are the so-called vascu- 

 lar na>vi, or strawberry marks, 

 which are usually congenital. 

 They are sometimes sharply 

 Circumscribed, and sometimes FIG. ISO.-ANGIOMA CATER*OSCM OF LITER. 



merge imperceptibly into the Tnis sec tion shows the entire small tumor. 



surrounding skin. They 



sometimes occur iu the mucous membranes, in the mamma, bones, and 

 brain. They are benign tumors, never forming metastases, but may be 

 associated w r ith sarcomata. 



2. The second form of hsernangioma, called angioma cavernosum (Fig. 



