CYSTIC TUMOURS. 441 



produce considerable thickening of the subcutaneous tissues of 

 the parts surrounding its course. The cyst sometimes becomes 

 consolidated, either from the treatment employed for its removal, 

 or from some other cause. The repeated application of iodine, 

 or its combination with mercury, will often reduce it very con- 

 siderably. In some cases a strong application, such as one dram 

 of the biniodide of mercury to the ounce of lard, will answer ; 

 in others, a frequent application of a milder preparation will 

 do best. I have found the following a very nice remedy: — 

 Hydrargyrum biniod., one drachm; water, twelve ounces; and a 

 sufficient quantity of the iodide of potassium to dissolve the 

 biniodide. This is to be applied once or twice a day until 

 slight soreness is produced, and reapplied when the soreness 

 disappears. If possible, the horse should be turned out to grass, 

 or kept in a thickly bedded box during treatment. 



Cysts upon the hock or elbow, or indeed upon any part of 

 the body, if they do not cause lameness, are not to be looked 

 upon as unsoundness. 



A form of capped hock arising from disease of the os calcis, 

 and an unsoundness, has been already described (page 312). 



In some rare instances collections of fluid-forming cysts occur 

 in front of the patella, the knees, and other parts of the body. 

 They may be opened with safety. 



In horned cattle immense cysts form in front of the knees, 

 caused by the animal being compelled to lie upon a hard floor. 

 A seton through their substance, and the application of a bandage, 

 to prevent bruising whilst the patient is lying down, will gene- 

 rally remove them. 



Serous cysts form in the ovaries, mammary glands of bitches, 

 in the thyroid body of all our patifents, and in the facial sinuses 

 of the horse and ox. 



The cystic growths which are found in the ovaries are either 

 simple or unilocular, compound or multilocular ; sometimes 

 scarcely increasing the normal size of the ovary, which is found 

 to have lost its natural structure, and its place taken up by a 

 number of small cysts ; they are supposed to result from dis- 

 tention of the Graafian vesicles by a morbid increase of their 

 contents. In other cases the cystic growths attain an immense 

 size, and hold a large quantity of fluid, which distends the 

 cavity of the abdomen, and presents a swelling externally which 



