TUMOURS AND CANCERS, 245 
to the gland from which it arose. Such a tumour is 
called an adenoma, and reccives a specific name accord- 
ing to the gland it resembles—sebaceous, mammary, renal, 
hepatic, &c. Adenomata may attain enormous size and 
weigh many pounds. As life advances the mimicry is 
crude, the cells, instead of clothing the alveoli in a 
regular manner, are tumbled together in confusion. Such 
tumours are cancers; they grow aimlessly, having no 
function to keep them in subjection, and being poorly 
supplied with blood vessels, undergo degenerative 
changes, and the cells being dispersed over the body 
may reproduce, in remote tissues and organs, secondary 
tumours resembling the original cancer from which they 
arose. 
The glandular nature of cancers is further illustrated by 
the fact that in their intimate structure they resemble 
the glands in the immediate neighbourhood. Thus a 
cancer of the lip resembles the cutaneous glands ; in the 
liver it mimics the liver ; mammary cancer resembles im- 
perfectly the secreting tissue of the breast, and so forth. 
Many competent pathologists are of opinion that 
cancers like the infective tumours are due to a micro- 
organism ; this is very probable, although thus far inqui- 
ries in this direction have not yet succeeded in identifying 
such agents ; nor is cancer inoculable from one animal 
to another. Should a bacterium be ultimately found as 
the causative agent, it will in no way affect the arrange- 
ment of cancers into a group apart from other tumours, 
as they exhibit in such a marked degree the glandular 
type of structure which alone serves to distinguish them 
from sarcomata, with which they were frequently con- 
