PEEITONITIS. 583 



qiient occiuTence tlian in association with tlie general and 

 often inappreciable agencies previously noticed. It may follow 

 the infliction of wounds penetrating, or non-penetrating, of the 

 abdomen, the performance of castration, the surgical treatment 

 of hernia and some other diseased conditions. 



5. Besides agencies strictly traumatic and operating from 

 without, peritonitis of a dangerous and most frequently fatal 

 ch.Sira.cter folloivs abdominal ruptures and perforations. The 

 chief of these in the horse are rupture of the gastric or in- 

 testinal walls, rupture of the liver and spleen, either of their 

 intimate structure or of an abscess or hydatid cyst which 

 they may contain ; bursting of similar accumulations in the 

 pelvis or gland-structure of the kidneys ; of the bladder from 

 over-distension ; or of collections of matter in natural situa- 

 tions or in adventitious products. 



b. Anatomical Characters. — With the full development of 

 the disease there is heightening of colour of the peritoneal 

 membrane, with perceptible increase in its thickness from 

 effusion amongst and gemination of its ultimate elements, to- 

 gether with extension of the same activities to the free surface 

 of the membrane. 



Rarely do we find this redness and hypera^mic condition of 

 the membrane of a uniform character, certain portions of it 

 having definite relations to particular organs being more dis- 

 posed to the unnatural action than others. Its usual appear- 

 ance is that of spots or streaks of greater or less extent 

 scattered over a variable surface, having a disposition to in- 

 crease by coalescence. 



In some instances where the activity of the process has 

 somewhat subsided, or where it never has been so active, there 

 may not be much redness, thickening being the only or the 

 most distinctive feature. 



With the early alteration of the free surface of the mem- 

 brane effusion of serum is a usual concomitant : this effusion 

 may be small in amount, or of such a quantity as to constitute 

 abdominal dropsy. The condition of considerable effusion 

 with much thickening of membrane without heightening of 

 colour is commonly observed in those cases in young horses, 

 the result of exposure and insufficient dietary. In the more 

 active forms we find that the effused material is not entirely 



