12 SCIENCE BULLETIN, No. 21. 



Selected portions of organs, etc., were placed in test-tubes, wide-mouthed 

 specimen bottles, &c., with the usual precautions, and taken back to the 

 laboratory for further work. Even after the utmost care some of the tubes 

 r bottles were subsequently found to be contaminated, no doubt by air-borne 

 organisms that gained entrance as the specimen was being placed in the 

 receptacle. Any such were rejected. As a rule, with every visit to the 

 affected localities during the season, one could always rely on obtaining 

 sufficient uncontaminated material for subsequent experimental work in the 

 laboratory. 



In this experimental work, sheep of any age over nine months were em- 

 ployed. The usual sites of the inoculations were the subcutaneous tissues of 

 the insides of the thighs, the chest and neck ; also the muscles of the former. 

 The inside of the thigh was preferred, however, on account of the ease with 

 which one could watch the development of the lesion clinically, it being 

 naturally devoid of wool, and capable of being manipulated post-mortem with 

 least fear of accidental contamination of the exposed tissues. With the 

 rabbit and guinea-pig, the inoculations were made subcutaneously and 

 intramuscularly, usually into the thigh. In the fowl and pigeon the sites 

 were the pectoral muscles. 



Young sporing cultures about twenty to twenty-four hours old were usually 

 employed, either in serum-formate broth or liver-piece broth. The cultures 

 from which these inoculation sub-cultures were made might, however, be 

 some months old. 



In cases autopsied immediately after death, the bacilli could be recovered 

 in purity from the local lesion and the exudate around it. In the following 

 notes on the experimental inoculations, it may be accepted that unless the 

 contrary is stated, the purity of the organisms from lesions so produced was 

 tested microscopically and culturally, and at times by inoculation into another 

 animal. In quite a number of cases it happened that no matter what care 

 was taken to regulate the dose of culture and the time of inoculation, the 

 animal would be found dead upon one's arrival in the morning. In the case 

 of sheep, although in some instances it was evident that death had not long 

 ensued, post-mortem invasion by other organisms had already taken place, so 

 that bacteriological work on that particular animal was rendered quite 

 nugatory on account of the character of the organisms being experimented 

 with, although the lesions themselves were not masked by post-mortem 

 phenomena. In the case of the smaller animals, those not killed or not seen 

 to die were discarded, and not used in the compilation of experimental data 

 or the drawing of conclusions. 



Sheep. 



The administration of relatively large amounts of young, virulent, sporing 

 cultures by the mouth has quite failed to produce any evidence of reaction, 

 although a number of methods were employed to facilitate the action of the 

 organism and to prevent its destruction* by the digestive agencies of the 

 animal. This is quite in conformity with the feeding experiments made with 

 minced organs, viscera, &c. ; of naturally affected sheep, as previously 



