354 
H. F. PALMER. 
cysts and neoplasmic cysts. The former consist in a distention 
and hypertrophy of a duct or secreting gland, the contents of 
which is the normal secretion more or less altered by retention. 
The latter are new formations which are the result of enlarge¬ 
ment of the primitive cell or areolar interspace. 
Retention cysts occur on the skin and subcutaneous cellular 
tissue. They are round and smooth in outline and free from 
pain. They are composed of sebaceous secretion, epithelial 
scales, oil globules, granular matter and crystals of cholesterin. 
To this class belong mucous cysts, sebaceous cysts, salivary 
cysts, distention of bursa, effusions into sheaths of tendons and 
muscles. 
Mucous cysts may appear anywhere on a mucous surface. 
They are tense globular swellings, occasioning ltttle or no 
pain, and are filled with viscid ropy mucous and epithelial 
debris. 
Sebaceous cysts are quite common in the human family, es¬ 
pecially among the females. Nearly all have recently seen 
specimens of these and the manner of their removal, so they 
need no further description here. . 
Salivary cysts are met with in connection with the ducts of 
the salivary glands. When these appear under the tongue on 
either side of fraenum lingui, they are then called ranula. 
Distention of bursa is quite common about the posterior part 
of the fetlock joint, and is known as wind-galls. They are soft 
symmetrical cysts of varying dimensions, painless and, except 
for their unsightly appearance, cannot be called an unsoundness. 
Distention of bursa may be seen better developed and caus¬ 
ing more inconvenience in the region of the hock. These cause 
lameness by their mechanical obstruction to the free movement 
of the joint. Among these may be noted thoroughpin, which in 
many cases is simply a distention of the bursa. 
All retention cysts are treated by producing absorption by 
means of stimulating applications. If this fails, tap the cyst, 
remove its contents, and scrape the internal membrane or inject 
a stimulating fluid into the sac after the contents is removed. 
