CHAPTER XIX. 



DISEASED GROWTHS. 



The limits of the present work forbid any systematic descrip- 

 tion of the various degenerations of tissue (fatty, mineral, amy- 

 loid, pigmentary, etc.), and of the tumours or diseased growths 

 which appear in different paits of the system. The last will 

 only be noticed so far as to point out the principal distinctive 

 characters of the malignant tumours or cancers, and the simple. 



Simple Tumours are composed of elements like those pre- 

 viously existing at the same or some other part of the body ; 

 they do not tend to draw surrounding structures into their 

 substance, but grow between these and push them aside ; 

 usually they are surrounded by distinct sacs, which separate 

 them completely from surrounding tissues except where the 

 blood-vessels enter; they do not tend to produce swellings in 

 the nearest lymphatic glands, by reason of propagation of 

 elements absorbed from the diseased mass, nor an unhealthy 

 constitutional state— dyscrasia— tending to the formation of 

 such diseased masses in internal organs ; and their elements 

 tend to be resolved mainly into fat or gelatine by boiling, 

 which shows there is little albumen in their structure. 



Cancers, on the other hand, usually contain elements unlike 

 any previously existing in the system. The presence of large 

 cells, each containing smaller ones (nuclei) in its interior, and 

 these still smaller nuclei (nucleoli), was at one time thought 

 characteristic of cancer, and though this cannot now be main- 

 tained, yet the abundance of such cells, or of any cells, imply- 



