MALIGNANT TUMOURS IN ANIMALS. 5gt 



central cells were infiltrated with fat globules or had undergone fatty 

 degeneration ; at several points these degenerated cells were sur- 

 rounded by other flattened cells arranged in lamellae (Fig. 94). The 

 third consisted of an epithelioma the alveoli of which contained small 

 rounded elements. Sections showed numerous cells resembling those 

 described by various authors as coccidia. We have several times 

 noted cells of this character, but in the above cases they were particu- 

 larly abundant and remarkable. Although the source of the cancer 

 was evident in the two first cases it was extremely doubtful in the 

 third. 



In passing we may also mention the various epithelial tumours 

 affecting the point of the elbow, thoracic walls, lung, thyroid body, 

 penis, and lips in the dog. In a cat we saw an epithelioma occupying 

 the thoracic wall, and the substance of the lungs. 



Though rarer than has usually been described, sarcoma is never- 

 theless fairly frequent in the dog. We found a round-celled sarcoma 

 in the elbow region, and a fusiform -celled sarcoma on the buttock. 

 We had under observation a nine-year-old sheep dog with complete 

 paraplegia, accompanied, however, by persistence of cutaneous sensa- 

 tion, due to a tumour which had destroyed the body of the first 

 lumbar vertebra ; it projected considerably into the neural canal, and 

 was almost as large as a fowl's egg. This tumour proved to be a 

 fusiform celled sarcoma (Fig, 95), containing tracts of osteoid tissue, 

 which stained rose-red with picrocarmine, and were pierced with 

 stellate cavities provided with canaliculi, resembhng in shape osteo- 

 plasts. 



In two horses we saw lesions resulting from repeated mechani- 

 cal injury. In one case a tumour, the size of a man's fists, had 

 developed on the anterior margin of the shoulder beneath the collar. 

 In another the grow^th had existed for two years. It was located on 

 the metatarsus of the near hind limb, a little above the fetlock, w-as 

 very large and ulcerated on the surface. It had returned after 

 removal. These new growths were not true tumours but chronic 

 inflammatory growths formed by fibrous tissue. We mention these 

 cases because without recourse to the microscope thev might have 

 been mistaken for cancerous tumours, the result of injury. The return 

 after operation and the ulceration of the surface might seem to justify 

 such a view. 



We have also seen tumours in three fowls. In one case the feet 

 were the seat of soft new growths. In the two others, numerous 

 tumours, varying in size between a haricot bean and a hazel nut, were 

 found in the liver, spleen, lungs, intestine, and peritoneum. These 



