TUMOURS OF THE LIPS AND CHEEKS. 
5 
they lie close under the mucous membrane, sometimes attain the size of 
a pigeon’s egg, and contain a thick, fluid, honey-like material. They are 
really retention cysts, produced by obstruction of the ducts of mucous 
glands. So long as they attain no considerable size, nor become the 
seat of inflammatory changes, they are seldom observed. To detect 
them, the thumb is laid on the external skin, the fingers on the mucous 
membrane of the lip, which is allowed to glide slowly through the fingers. 
When such tumours become inflamed, they cause enlargement of the sub¬ 
maxillary lymph glands, displace the lips, and impart to the face some¬ 
what of the appearance of facial paralysis. If they become inflamed, or 
interfere with feeding, treatment will be required. It is generally suffi¬ 
cient to lay open the parts and dress the interior with nitrate of silver, 
sulphate of copper, 2 per cent, 
corrosive sublimate solution, or 
10—20 per cent, solution of chloride 
of zinc. 
A typical tumour develops above 
the base of the false nostril in 
horses, usually resulting from 
occlusion of a sebaceous follicle. 
It is filled with a granular material. 
It may become as large as a hen’s 
egg, is round, painless, and freely 
movable, but seldom causes any 
difficulty in breathing. By passing 
the finger into the false nostril, it 
may be readily felt, and is some¬ 
times visible from without. (Fig. 1.) Such growths are seen oftenest 
in young foals. They are easily removed. The animal is cast—though 
in very quiet subjects this is scarcely necessary—and an incision 
made through the skin in the long direction of the head. The tumour 
is then grasped with forceps and freed from its surroundings, care 
being taken not to incise it, as its removal is thus rendered more difficult. 
Should such an accident happen, a dark-grey, granular material is dis¬ 
charged, and the inner wall of the tumour comes in view. The nasal 
mucous membrane being firmly adherent to the swelling may he injured, 
when froth from the nostril will appear in the wound. But even where 
the mucous membrane has been cut, healing by primary intention 
occurs. The wound is at once sutured, and finally covered with iodo¬ 
form collodion or wound gelatine. Tempel removed a dentigerous cyst 
from a horse’s upper lip. With the exception of those named, new 
growths on the cheeks and lips are comparatively rare in domesticated 
animals. Fibromata, sarcomata, carcinomata and melanomata have 
