50 Veterinary Medicine. 



and the mononuclear cell taking in one which the polynuclear re- 

 fuses. 



The small round white cells (lymphocytes) and the eosinophile 

 leucocytes take no prominent part in phagocytosis. 



EXUDATION. 



In inflamed vascular tissues one of the most important results 

 is the exudation. This is not, however, a mere transudation of 

 the liqnid parts of the blood, as takes place in dropsy, but it is to 

 a large extent a selective process determined apparently by the 

 condition of the capillary walls, and the nature of the inflamma- 

 tion is stated according to the character of the exudate. The 

 dropsical effusion contains little albumen, fibrine or cell forms, 

 and does not coagulate. The inflammation-exudate contains 

 abundance of fibrine, cells and other solids and coagulates spon- 

 taneously in contact with inflamed tissue, or when removed from 

 the body, by reason of the transforming leucocytes. Inflamma- 

 tory exudate usually contains 6 to 8 per cent, of solids whereas 

 the normal canine lymph contains 4 to 6. The exudate varies 

 not only in different inflammations, but in successive stages of 

 the same inflammation. The exudate may be mucous, serous, 

 fibrinous or hsemorrhagic. 



Mucous Exudate. In inflammation on a mucous or synovial 

 surface the inflammatory exudation, mingled with the more or 

 less altered secretion of the mucous glands, and the epithelial cells 

 and leucocytes, forms a viscid fluid, rich in mucin, and character- 

 izing the mucous or catarrhal inflammation. The nature of the 

 discharge varies greatly, the serous character predominating at 

 the start of the inflammation, and a thick, opaque creamy or semi- 

 solid niuco-purulent material appearing as the disease advances. 

 It contains filaments of precipitated mucin insoluble in acetic 

 acid or alcohol and cells in all stages of change from the exuda- 

 tion leucocyte and mucous cell to the pus corpuscle, the latter be- 

 ing characterized by its bipartite or tripartite nucleus rendered vis- 

 ible by contact with weak acetic acid. 



Serous Exudate. This consists of the liquid elements of the 

 blood with only a limited amount of fibrine formers and conse- 

 quently little tendency to clot firmly. The presence of fibrinogen 



