288 



SPECIFIC MICRO-ORGANISMS 



Pig. 115. — Cli perfringens in agar 

 culture, showing gas formation.- 



showing general emphysema of the 

 tissues and gas bubbles in the blood- 

 vessels. They obtained cultures by 

 anaerobic methods and caused similar 

 post-mortem emphysema in the bodies 

 of rabbits. The organism lives and 

 multiplies in the intestine of m.an and 

 other'mammals, is widely distribtited 

 in the soil and is commonly present 

 in milk and other animal food prod- 

 ucts. The cell is a large rod sur- 

 rounded by a capsule when grown 

 on media rich in protein or in the 

 animal body. The width of the cell 

 (without capsule) varies^ from i.i 

 to 1.7/* with a mean of 1.3/i and the 

 length from 2.6 to 7.6^, with an 

 average of 4.6/1, the measurements 

 being made on organisms grown in 

 an agar stab-culture 24 hours at 

 37° C. When grown in blood broth 

 the germ is capsulated "and the 

 measurements, including the capsule 

 are as follows: width 1.9 to 2.5/* with 

 average of 2.1/i and length, 2.8 to 

 6.6iu with average of 4.7/1. Usually 

 the organism is non-motile, but flag- 

 ella can sometimes be demonstrated. 

 In the intestine and in protein media 

 the organism forms spores, usually 

 median without bulging of the cell, 

 but these are not commonly observed 



' The measurements are taken from Kerr, The Bacillus wel'chii, Thesis, Univ. 

 of Illinois, 1909. 



