BUREAU OF ANIMAL INDUSTRY. 675 



4. Same mode of inoculation destroys 4. Guinea-pigs somewhat more refrac- 

 guinea-pigs, with a few exceptions. Le- tory; extensive local lesions as in rab- 

 sions quite the same as in rabbits. May bits; occasionally plastic peritonitis; die 

 live fourteen days. in four to six days; spleen not enlarged. 



5. Pigeons destroyed by large doses. 5. Pigeons also susceptible to large 

 Bacteria in internal organs. doses. Bacteria absent from internal 



organs. 



6. No fowls destroyed by inoculation. 6. Large doses kill fowls. Very ex- 



tensive local intilfcration and destruction 

 of muscular tissnie. 



7. Pigs are either not affected by hypo- 7. Large doses cause acute Bclerosis of 

 dermic injection, or else a severe disease liver, with icterus, Bacteria absenj;. 

 follows, characterized by hemorrhages in 



all organs. Bacteria present in large 

 numbers in internal organs. 



8. Feeding culuu-es after starving for 8. Feeding cultures produces no effect 

 a day produces extensive necrosis of mu- whatever. 



cous membrane of large intestine; in- 

 flammation and occasional ulceration of 

 stomach and ileum. 



The inoculations apply to subcutaneous injections of small quantities of liquid 

 cultures, in mammals on the inner aspect of the tliigh, m birds on the i^ectoral. 



MORE RECENT OUTBREAKS OF INFECTIOUS PNEUMONIA.* 



Recently specimens were received from an outbreak of infectious 

 pneumonia in Iowa. According to information obtained by Dr. N. 

 H. Paaren in January, 1887, a disease of swine prevailed during the 

 fall and winter of 1885-'86, and during the same period of 1886-87, 

 which was limited chiefly to the four counties of Worth, Mitchell, 

 Cerro Gordo, and Floyd, along the Shell Rock River. Specimens of 

 lung tissue were obtained from Cerro Gordo County, although the 

 disease was almost extinct at this time (January, 1887). 



At Mason City Dr. Paaren examined a number of dead hogs at a 

 soap factory, which had been brought together from different parts 

 of the surrounding country. In these animals the lungs were uni- 

 formly diseased, the digestive tract normal or but slightly congested. 

 The liver also was diseased in all examined. 



From these observations it would seem that the disease prevalent 

 in Iowa was the infectious pneumonia which has been described in 

 the preceding pages, and not the real hog-cholera. The following 

 experiments tend to confirm these views : 



Pieces of lung tissue sent from Cerro Gordo County were partly 

 immersed in a blood-stained liquid which must have exuded from the 

 lungs. The animal was frozen solid when the tissues were removed. 

 Both pieces of lung tissue had a faint, not putrescent odor. They 

 weiw of a red flesh color. The tissue seemed completely airless. 

 Cover-glass preparations showed the infiltration to be made up 

 almost exclusively of small round cells, with an occasional epitheloid 

 ceil amongst them. Careful observation demonstrated the presence 

 of very minute oval bacteria, varying slightly in length. The long- 

 est (perhaps not more than 1"™) stained only at tne extrepiities. 

 There were no other bacteria visible to indicate any advanced decom- 

 position. In one of the pieces the knife had been passed through 

 an irregular cavity in the lung substance as large as a marble, lobu- 



* Lately a disease of the lungs, probably identical with the infectious pneumonia 

 under discussion, came to om- notice in the District of Columbia, from which the 

 same microbe was obtained. A detailed account must be reserved for future pub- 

 lication. 



