128 Veterijiaiy Medicine. 



ular, and throws out a free serous secretion. Thus hydrocepha- 

 lus is a usual concomitant of the affection. 



The disease is characterized b}' its slow advance in keeping 

 with gradual increase of the tubercle and is thus distinguishable 

 from tlie more acute congestions and inflammations. The earlier 

 stages are usually marked by nervous irritability, hypersesthesia, 

 intolerance of light, closed eyelids, congested conjunctiva, grind- 

 ing of the teeth and even spasms partial or general. The second 

 stage shows somnolence, deepening into stupor or coma, or there 

 ma}' be going in a circle or other irregular movement. Squint- 

 ing usually convergent, dilated pupils and congestion of the optic 

 disc frequently occur. The .sleep, stupor, paraly.sis or coma may 

 set in early and is usually largely due to the amount of exudation 

 and the rapidity of its effusion. 



TUMORvS OF THE BRAIN. NEOPLASMS. 



Existence inferential with similar external tnmors. Cholesterine tumors 

 on plexus of lateral, third or fourth ventricle : pea to egg : in old ; con- 

 centric layers with abundant exudate. Symptoms : slight, or excitability, 

 dullness, vertiginous paroxysms with sudden congestions, as in encepha- 

 litis, sopor, stupor, paresis, coma. Melanoma : mainl}' meningeal ; pea to 

 walnut ; with skin melanomata in gray or white horses. Cases. Pigmented 

 sarcomata. Diagnosis, inferential. Psammoma : advanced cholesteatoma, 

 melanoma, fibroma, etc. : osteid tumors. Nervous irritation, delirium, 

 spasms, nervous disorder, and paroxysms. Myxoma : contains mucin : 

 cells (in homogeneous matrix) round, spindle-shaped or stellate. Changes 

 to fat (cholesterine). Qjdematous connective tissue, neoplasm. -.Myxo- 

 lipoma. Myxo-cystoid. Symptoms. 



Tumors in the brain are not marked by distinct pathognomonic 

 symptoms, so that their presence is to be inferred as a probabilit}' 

 rather than pronounced upon as a certainty. 



The most common forms in the horse are cholesterine (choles- 

 teatoma), melanotic (melanoma), sandy, grittj^ (psammoma), 

 and fibrous (fibroma). 



