370 BOVINE PATHOLOGY. 



very similar, except that the retractor muscle is even more 

 powerful, and the lachrymal and Meibomian glands are 

 very well developed, as also is the Harderian gland, which 

 is situated inside the cartilago-nictitans, and secretes a lu- 

 bricating fluid. The ductus ad nasum does not extend so 

 far down as the anterior naris. We have already noted the 

 frequent presence of bony tumours on the margin of the orbit. 

 Fractures of this part are not rare as a result of various 

 kinds of injuries ; either a small portion of bone is chipped 

 off the edge, or the orbital frontal process may be entirely 

 fractured. Loose portions of bone must be removed 

 artificially, or will slough out, and the attachments of the 

 eyelid may be interfered with, or depression of the frag- 

 ments may exert pressure on the contents of the orbit. 

 A highly vascular encephaloid or medullary sarcomatous 

 growth sometimes commences at the back of the orbit, and 

 grows rapidly, pressing on the optic nerve, and forcing 

 the eyeball to one side. It appears at the surface as a 

 highly vascular mass, and is termed Fungus H^matodes. 

 It produces complete loss of sight, and must be treated by 

 extirpation of the contents of the orbit, and subsequent 

 application of the actual cautery, to restrain haemorrhage 

 and destroy the last vestiges of the cancerous mass. The 

 patient should then be fattened for slaughter. This is 

 perhaps the most frequent cancerous growth in the ox. 



Laceeations of the Eyelids must be treated on the 

 principle of not removing any part which can possibly be 

 saved. Youatt tells us that '* the eyelids are more subject 

 to disease in the ox than in any other domestic animal," 

 and mentions Spontaneous Emphysema of the organs to be 

 cured by puncture ; and also (Edema, which is a sign of 

 general debility, or may be a sign of the existence of some 

 irritant in the eye. Sometimes cases of this kind lead to 

 chronic thickening. 



Warty Growths are sometimes seen on the eyelids, and 

 must be snipped off, and their roots touched with caustic. 

 Finally, the largely developed Meibomian glands may 

 become inflamed or their ducts blocked up, and a small 

 abscess results. When this bursts or is opened the parts 



