STREPTOCOCCUS OF STRANGLES 97 



matter, formed only in the presence of oxygen, which is soluble in 

 chloroform. 



Pathogenesis. This bacillus is pathogenic for guinea-pigs and 

 rabbits 1 c.c. of a bouillon culture causing the death of the animal in 

 from 12 to 36 hours. Smaller amounts do not kill the animals, but 

 render them immune to doses fatal to animals not previously 

 protected. In rabbits inoculated with a culture of the Bacillus 

 anthrax a fatal result may be prevented by soon after inoculating 

 the animal with a pure culture of the Bacillus pyocyaneus. Wood- 

 head's experiments indicate that the antidotal effect is due to the 

 chemical products of the growth of the bacillus and not to an 

 antagonism of the living bacterial cells. 



STREPTOCOCCUS OF STRANGLES OF THE HORSE 



(SCHUTZ) 



(Ger. Druse der pferde ; Fr. Gourme.) 



This is an infectious catarrh of the upper passages of the horse, 

 with suppurative inflammation of the neighbouring lymph-glands, 

 generally forming an abscess. The disease is often complicated with 

 metastatic abscesses in other distant organs and lymph-glands, the 

 virus being carried by means of the blood and lymph circulation. 

 One attack gives immunity for years, perhaps for a lifetime. 



Microscopical Appearances. The Schiitz streptococcus is found in 

 the pus obtained from the lymph-gland abscesses in more or less long 

 bundles of chains. The most significant formation is when the cocci are 

 arranged in threads resembling a wreath of roses, lying either slightly 

 bent or undulating between the pus corpuscles (see Photomicrograph, 

 Plate IV., Fig. 23). Individual cocci in the chain sometimes appear 

 larger than the others. 



Staining Reactions. The streptococci stain very well with 

 fuchsin and gentian violet. For pus preparations the Cladius method 

 gives good results, also the Gram method, the decolorizing being 

 accomplished with a saturated alcoholic solution of fluorescin according 

 to Kiihne's modification. 



Biological Characters. On Gelatine the growth is weak, white 

 colonies forming on the inoculation stab. The gelatine is not liquefied. 



On Agar-Agar, inoculated with a drop of pus, numerous visible trans- 

 parent colonies about the size of a pin-head develop. In stab cultures 

 at 31 C., they form a greyish-white zone with wing-like projections. 



On Solid Blood Serum at 37 the growth is most luxuriant. The 



G 



