664 REPORT OP THE COMMISSIONER OF AGRICULTURE. 



patches visible on tlie pleural surfaces and in tlie parenchyma. These 

 were evidently extravasations into the alveoli, and etioiogically the 

 same as the extravasations found elsewhere. In the majority of cases 

 lung lesions were entirely absent. When present they were usually 

 associated with an abundance of lung worms in the bronchi. In 

 many cases the small anterior lobes resting laterally upon the peri- 

 cardium were collapsed (atelectasis), of the color of red flesh. This 

 condition seems to stand in no direct relation to the disease itself. 



The broncho-pneumonia found in the pigs above referred to ex- 

 tended over at least one-half of the lungs, involving the caudal por- 

 tion of the base, resting on the diaphragm. The pleura was but 

 slightly affected; a few adhesions and a more than normal quantity 

 of serum on its surface constituted the visible changes. The lung 

 tissue itself was airless, solid, of a grayish red, somewhat mottled. 

 From the pleural surface of No. 2 two tubes of gelatine were inocu- 

 lated by dipping into them a loop of platinum wire filled with serous 

 exudate. The heat of the weather liquefied both tubes soon after, 

 and within a few days the gelatine in one of them was densely 

 crowded with small whitish points; in the other tube the colonies 

 were fewer in number and consequently much larger. Both were, 

 in fact, pure cultures of a non-motile oval bacterium, found identical 

 in all respects with the microbe obtained from Geneseo, 111., and 

 already described. 



Postponing the description of this microbe for the present, the fol- 

 lowing experiments were made in order to determine its pathogenic 

 effect upon small animals: 



From one of the original tube cultures in gelatine, plate cultures were made, and 

 from one of the colonies a tube containing 10'^'^ beef -infusion peptone was inoculated. 

 When two days old the following animals received subcutaneously portions of this 

 culture: Two mice, |'=% -i^""; two rabbits, i"", i"*; two pigeons, i"", f "; two pigs, 4.5", 3". 

 One of the mice was dead on the following day. In the spleen and Uver were present 

 oval bacteiia and some quite long rods. The liquid culture from the blood remained 

 sterile. The second mouse died in two days. A peculiar bacterium was present in 

 spleen, liver, and blood, often irregularly fusiform and pyriform; most were cocci in 

 pairs. A liquid culture from the blood of the heart contained the inoculated microbe 

 only, and the identity of this germ with the one injected was confirmed by plate 

 cultures. 



Both inoculated pigeons died, one two days and the other four days after inocula- 

 tion. In the former the pectoral muscle at the point of inoculation had a grayish- 

 yellow parboiled appearance over an area of 1 to l-J square inches and extending to a 

 depth of three-eighth inchs. In the second bird, which had received the larger dose, 

 the local lesion was less marked. A thick pasty deposit had formed between the 

 skin and muscle, slightly infiltrating the surface of the latter. No bacteria could 

 be detected on cover-glass preparations in the blood or liver of either bird. 



Both rabbits likewise succumbed, one four and the other five days after inocula- 

 tion. The autopsies point out the radical differences between the hog-cholera bac- 

 terium and the coccus under consideration. Before death both animals lay on their 

 sides, breathing slowly. In the one which died first (which had received the smaller 

 dose) the inoculated thigh was enlarged and drawn up to the body, the fascia cover- 

 ing the muscles of the thigh and the contiguous abdominal wall were thickened into 

 whitish opaque sheets; a small area of the thigh muscles was whitish, necrosed. In 

 the abdominal cavity strings and flakes of coagulated fibrin m various parts, together 

 with the reddened appearance of the peritoneum, indicated a severe peritonitis; the 

 liver w^as dark, blood flowing freely on section; spleen scarcely enlarged. Beneath 

 the serosa of large intestine a few patches of extravasation; kidneys deeply reddened 

 to the tip of the papilla; lungs normal. The microbe was very abundant in the local 

 infiltration, the peritoneal exudate, in the parenchyma of spleen, liver, and kidneys, 

 as well as in blood from the heart. In these cover-glass preparations involution 

 forms were very common. Liquid cultures from blood of the lieart and the peri- 

 toneal exudate contained the microbe as it usually appears in liquids. Tube cultures 

 in gelatine from the blood, peritonal exudate, and liver contained very many colonies, 

 growing in a somewhat characteristic manner, to be described later on. 



