70 Bulletin No. 207. 



gested. Heart bright red in color and the wall at apex and 

 areas about coronary artery showed hyperaemic areas accom- 

 panied by ecchymoses. Stomach apparently normal. Ramifi- 

 cation and injection of the outer wall of the small intestine, 

 with areas of ecchymoses (Fig. 12). The mesentery highly 

 ramified and the lymph nodes swollen and congested. The inner 

 wall presented localized areas of hemorrhagic enteritis; it was 

 injected and ramified and showed rupture of capillary vessels 

 (Fig. 13) and enterorrhagia. Contents were of a watery con- 

 sistency tinged with blood. To the inner wall a sticky mucus 

 adhered. External wall of caecum apparently normal. On 

 the inner wall localized areas of hemorrhagic enteritis, not as 

 pronounced as in small intestine. Outer wall of colon appar- 

 ently normal, while inner wall showed numerous scattered punc- 

 tate hemorrhages. Liver congested. Spleen greatly enlarged; 

 ecchymotic hemorrhages on the capsule. Parenchymatous tis- 

 sue soft, dark and friable. Parenchymatous tissue of kidneys 

 soft and friable. 



Plantings in alkaline pork broth were made from the blood 

 and internal organs and incubated at room temperature under 

 anaerobiosis. An anaerobic organism was isolated from the cae- 

 cum which possessed characters similar in morphology and 

 pathogenicity to the bacillus c-91 used to infect this animal. 

 As recovered from horse No. 94 this organism proved fatal to a 

 guinea pig in 25 hours in a dose of 0.5 cc. by the mouth (Fig. 

 14). Preceding death, salivation and prostration were ob- 

 served in this pig. Autopsy showed engorgement of the liver, 

 areas of congestion in the lungs, softening of a portion of the 

 membrane of the inner wall of the stomach and small intestine, 

 accompanied by areas of injection. 



Botulism Antitoxic Serum. 



Following the demonstration of the production of an ex- 

 tracellular toxin by B. botulinus, van Ermengem observed in 

 preliminary studies that animals recovering from an artificial 

 infection evidenced some tolerance to a second injection, thus 

 pointing out the possibility of the development of a specific 



