TUMORS, 218 
or given only doubtful results. The numerous experiments that. we have 
been making for the last four years for the purpose of transferring neo- 
plasms from man to’ the dog, from horses to horses and dogs, from dogs 
to dogs, rabbits, guinea-pigs and hens, and from chicken to chicken,—all 
have failed completely: we have not even succeeded when trying to graft 
upon cancerous dogs fragments of their own tumor. Let us add, however, 
that we have transferred to three dogs, by rubbing the mucous membrane 
of the penis, papillomatous vegetations developed on the penis-of another 
dog; but these productions remained local, decreased and disappeared 
of themselves. If these negative results do not allow one to deny the 
parasitic nature of cancer, they suggest changes in the experimental 
methods, since they tend to demonstrate that it is not by increasing the 
inoculations made in the ordinary way that the problem is to be solved. 
In man some observations have been mentioned which seem to establish 
the contagiosity of cancer; we have never observed anything like it in 
animals.” ? 
In animals, as in man, tumors may appear on parts the most different, 
but they have a well-marked predilection for the skin, some mucous mem- 
branes and glands, the mamme in particular. The testicle is, after the 
mamme, the organ most often affected. The ectopia of this gland pre- 
disposes it to neoplastic degenerations: cancer of the testicle is quite com- 
mon in monorchid and cryptorchid horses. Neoplasms are also quite 
common in the mouth, nasal cavities, sinuses, on the penis, the tail, the 
arms, on the inferior regions of the extremities, on the eye, in the thyroid 
or parotid glands, and on bones. Cancer of the tongue is extremely rare 
in animals; that of the lips is sometimes seen in old dogs; that of the 
uterus, socommon in woman, is exceptional in female domestic animals. 
All visceral cancers are much rarer than was formerly believed. Ina 
great number of observations made upon tumors of the thoracic or abdomi- 
nal organs, the lesions revealed in reality tuberculosis. This error has 
been current for a long time in the case of dogs, where tuberculosis is 
ordinarily manifested by large products developed in the viscera (liver, 
lungs, kidneys), lymphatic glands and serous membranes. It may yet 
persist, even with histological examination, which reveals a structure 
resembling sarcoma or lymphademia more than tuberculosis ; it is only by 
the discovery of the bacilli and inoculation that the true nature of these 
products can be made out. Cancer of the liver and of the kidneys are 
the only ones which are frequently met with; that of the stomach is 
exceptional. In the inquiries which we have been making for several 
years, we have found, in the dog, several series of 10, 12, 15 cases of 
1 Cadiot, Gilbert and hoger ; Les tumeurs malignes chez les animaux.—Presse 
Medicale, 1894, p. 219. 
