272 



THE MICROSCOPIST. 



Soon after vessels are formed in the thrombus, which 

 give it an organlike connection with the body, as other 

 pathological new formations. These vessels may widen 

 and become cavernous, as in Fig. 221, and as the walls 

 become thinner and finally disappear the thrombus ceases 

 to exist. 



FIG. 221. 



a 



From the cross-section of an arterial thrombus of three months, a. Media, only the 

 innermost layers, b. Boundary lamella of the media and intiiua. c. Intima. d. Bound- 

 ary of intiiua towards the thrombus, e. Thrombus. /. Lumina of vessels. Distinct 

 epithelium. 1-300. After RINDFLFISCH. 



The softening of the thrombi is a 'dangerous process. 

 Fragments may be carried from the radicles of the vena 

 cava through the right heart to the lungs ; from the radi- 

 cles of the pulmonary veins through the left heart to the 

 various organs of the body ; or from the radicles of the 

 portal vein to the liver. Such particles may occlude the 

 vessel in which they are found, producing embolism, the 

 results of which may depend on the mechanical obstruc- 

 tion to the circulation (anaemia and softening), or on 

 the irritating or infective properties of the emboli (pyae- 

 mia). 



a. Adenoid or Eeticular Connective Type. 



1. Lymphoma. This is a new formation of lymphatic 

 or adenoid tissue, and is generally found as small tumors 

 or infiltrations, consisting of rounded bright nuclei, and 



