52 Veterinary Medicine. 



lecular degeneration (Cornil and Ranvier), or development into 

 new tissue (Paget). When organized it usually takes the form 

 of the adjacent tissue from which its trophic cells are derived. 

 Thus in divided tendons, in serous membranes and in granulating 

 wounds it is fibrous, and between the ends of a broken bone 

 it is osseous. If however, the adjoining tissue is a highly organ- 

 ized one, like nerve or muscle it may be replaced by a simpler 

 (fibrous, osseous). 



Fibrinous inflammations are especially found in connection 

 with inflamed fibrous tissues and in strong vigorous subjects. 



Blood Exudations. In all inflammations there is some mi- 

 gration of blood globules (red as well as white) but seldom in 

 quantity sufiicient to stain the tissues materially. Minute ruptures 

 of the capillary vessels are not uncommon, with punctiform clots 

 in the tissues, but extensive escape of blood is mainly seen in 

 penetrating or contused wounds of the loose, subcutaneous con- 

 nective tissue, and in infective inflammations (anthrax, Rinder- 

 pest, swine plague, petechial fever, malignant catarrh, snake- 

 bites) with destruction of blood globules or extreme changes in 

 the walls of the capillaries. Newly formed vessels in a friable neo- 

 plasm are subject to blood effusions. In acute inflammations of 

 serous membranes the exudate is usually of a dark port wiue hue 

 at first. In such cases it may pass in succession through all 

 the stages of dark red, brick red, yellow, reddish, and chocolate 

 color, before becoming milky and finally transparent. 



Croupous Exudate. Croupous inflammation usually occurs on 

 or near a mucous surface and is characterized by an exudation 

 consisting mainly of fibrinous material entangling white cells, 

 epithelium, a few pus corpuscles and some form of bacteria. In 

 true diphtheria of children this is the I^oifler bacillus, in the pseudo- 

 diphtheria, attending on scarlatina, etc., it is often streptococcus 

 pyogenes, in the diphtheria of calves it is bacillus diphtherise vitu- 

 lorum, and in that of chickens and pigeons it is the bacillus diph- 

 theriae columbarum (I,6fHer). Pseudomembranous inflammations 

 therefore constitute a group agreeing in the nature of the exudate 

 but differing essentially in the cause. This difference in the cause 

 has a most material effect on the course and gravity of the disease. 

 One form like true diphtheria in man not only extends into the 

 tissues, and tends to necrotic changes, but also poisons the nerve 



