Contagious Pneumonia in the Horse. 133 



starting point of disease, in this and influenza, making the sys- 

 tem very receptive of the streptococcus of strangles and of other 

 bacteria, the identity of which determines the nature of the 

 malady. The diplococcus or streptococcus of Schiitz in his 

 opinion is none other than the strangles streptococcus which, find- 

 ing a congenial home in the animal invaded by his cocco-bacillus, 

 pervades the system and determines the pathological phenomena 

 of contagious pneumonia. 



There are certain obstacles to the unreserved acceptance of 

 I^ignieres' conclusions, among the chief of which is the absence 

 of evidence that horses, successfully inoculated with his cocco- 

 bacillus in pure cultures, can infect others standing near them 

 with the same rapidity and certainty, as does the casual case of 

 influenza, or even of contagious pneumonia. The same holds true 

 of the supposed identity of the streptococcus and that of strangles. 

 Abscesses containing s'treptococci, were formed in the seats of 

 inoculation with Schiitz's organism, but there is no evidence that 

 the horses suffering from such abscess affected susceptible horses 

 standing beside them, as do ordinary cases of strangles. The 

 cocco-bacillus may be a concurrent cause of contagious pneu- 

 monia, but we need more proof to show that it is the essential 

 cause, even as we need proof of the absolute identity of the 

 streptococcus of strangles and brustseuche. 



Lesions. The pneumonia is far more likely to be double than 

 in the fibrinous form, and the area invaded, in its ratio with the 

 high intensity of the fever, is usually less. The consolidations 

 are especially common near the lower borders of the anterior parts 

 of the lungs. There may, however, be a number of centres in 

 each lung to be accounted for by the inhalation of the germ and 

 the starting of the morbid process at the various points on which 

 it falls. This, like the double character of pneumonia is therefor 

 in keeping with the contagious origin. Each centre of condensa- 

 tion shows a small area, hepatized, purulent or necrotic, with a 

 surrounding zone of dark bluish red congestion. The consoli- 

 dated areas are less dry and granular than in fibrinous pneumo- 

 nia, seeming to be largely infiltrated with a still liquid exudate 

 and dark blood, and thus tend to a greater tenacity, and less 

 friability. Black areas of infarction form in the lung, the throm- 

 bosis of the arteries, cutting off the free normal circulation and 



