MORBID ANATOMY 45 



elongated forms are observed. It is an aerobe, and a faculta- 

 tive anaerobe. When cultivated on artificial media it does not 

 liquefy gelatin, it does not change the appearance of milk, but 

 causes slight acidity and thickening of the lower stratum with- 

 out coagulation of the casein. The reaction of alkaline bouil- 

 lon is changed to an acid one and it does not give a visible 

 growth on potato. It stains by Gram's and Gram-Weigert's 

 method. In bouillon it grows in somewhat flaky masses while 

 the medium remains clear. It was fatal to fowls, mice, rabbits 

 and swine ; guinea pigs, dogs and sheep were not destroyed by 

 inoculation. This organism has not been given a specific 

 name. 



§ 39- Symptoms. It is not at all uncommon to find the 

 fowls dead and lying under the roosts. Occasionally capons 

 were observed to be sick for from 12 to 24 hours prior to 

 death. In these cases the feathers become rufiied and the fowl 

 showed evidence of extreme depression. The onset of the dis- 

 ease is very sudden and its course a very rapid one, usually 

 terminating in death. 



§ 40. Morbid anatomy. The authors describe the mor- 

 bid anatomy as follows : "The spleen is more or less enlarged, 

 showing hyperplasia of the Malphigian corpuscles. The pulp 

 contains numerous areas of extravasated blood. When a stained 

 section is examined by means of a hand lens a number of cir- 

 cular semi-transparent foci, the size of a pin hole, may be noted. 

 These are found on microscopic examination to be centers of 

 necrobiosis, consisting of parenchyma which has undergone 

 coagulation necrosis, and surrounded by a more or less well 

 defined capsule of embryonic and further developed connective 

 tissue cells and filaments. 



On microscopic examination, the kidneys show slightly 

 swollen epithelial cells of a beginning parenchymatous degen- 

 eration to the well pronounced disintegration of the renal 

 epithelium of acute nephritis. The degree of degeneration 

 depends, as a rule, upon the course of the disease. If a bird 

 succumbs suddenly or in the course of a few hours the morbid 

 changes are either not apparent at all or but slightly pro- 

 nounced, while, on the other hand, the duration of three or 



