EXAMINATION OF MORBID GROWTHS. 675 



&c., and the effects of different reagents, should he carefully 

 observed, and noted in a hook kept for that purpose. 



Cancer and Cancroid G-rowths. " Cancer, or carcinoma, is a 

 vascular, morbid production, characterized by a form of organic 

 cell, which is peculiar, and never enters as a constituent in any 

 normal tissue. It is usually deposited in the form of tumors, 

 but occasionally as an infiltration, in any of the organs of the 

 body, and the circumstances which give rise to its development 

 are yet unknown to us. 



There are several varieties of cancer, and the physical ele- 

 ments which ordinarily enter into their composition are as 

 follow : 



1. The characteristic cancer-cells, which are spherical, ovoid, 

 irregularly polyhedral, and frequently exhibit caudate prolonga- 

 tions. They average about the *02 mil. in diameter, and possess 

 finely granular contents, with a round or oval nucleolated nu- 

 cleus, as large or larger than a pus-corpuscle. Sometimes can- 

 cer-cells are double the ordinary size, or more, and not unfre- 

 quently contain several nuclei, or even other cells, constituting 

 parent or endogenous cells. 



2. Nuclei, which are spheroid or oval, and resemble those 

 within cancer-cells. 



3. Granules, and amorphous liquid or semi-solid matter. 



4. Fusiform or fibro-plastic cells. These are liable to be con- 

 founded with the characteristic cancer-cell, but usually may be 

 distinguished by the smaller nucleus, and the disposition to 

 elongate at opposite extremities, and pass from this condition 

 into the form of bands or fibres. 



5. Fibrous tissue ; most usually of the white variety, but not 

 unfrequently mingled with elastic fibres. 



6. Black pigment, in granules, or contained within cells. 



7. Fat, in granules, globules, and in the form of adipose cells. 



8. Vessels. 



The varieties of cancer are encephaloid, or medullary carci- 

 noma, scirrhus, colloid, melanosis, and fungus heematodes. 



Encephaloid is that form in which the cancer-cell predominates 

 over every other constituent. Occasionally, the cancer-cells 

 exist in it to the exclusion of all other matters, except liquid, 

 granules, and vessels. 



In scirrhus, fibrous matter predominates, and encloses the 

 cancer-cells within the areolae. 



Colloid is composed of a fibrous stroma, with loculi, filled with 

 a gelatinoid matter and cancer-cells. 



Melanotic cancer consists of any of the preceding forms, com- 

 bined with black pigment. 



Fungus haematodes is a term applied to an unusually vascular 

 form of cancer, or to any of the other varieties when they are 

 ulcerated and liable to bleed. 1 



1 Prof. J. Leidy, in Gluge's Atlas of Histological Pathology, Amer. Ed. p. 69. 



