158 BACTERIOLOGY. 



septic odour is produced by this bacillus in a 

 nourishing liquid. Cloudy masses are found on the 

 surface of the liquid, which later form a thick dry 

 pellicle. The latter consists of bundles of threads 

 matted together. The formation of ellipsoidal 

 spores occurs in the usual way; they measure 

 2*5 2 '8 IJL long, and more than i p. wide. The 

 bacillus is found on rotting eggs, and can be culti- 

 vated on boiled white of egg. It is closely allied 

 to the bacillus subtilis. 



Bacillus tumescens, Zopf.* Cocci, long and 

 short rods. They form a jelly-like disc, '5 i cm. 

 in diam., on slices of boiled carrot, with the 

 appearance of a rather tough crumpled skin of a 

 whitish colour. Examination of this pellicle shows 

 that it is formed of rows of rods lying closely 

 together. These rods can be observed to divide 

 into short rods and cocci. Spore formation occurs 

 in two stages of development, viz., in the cocci 

 and in the short rods. A cultivation is obtained by 

 exposing slices of boiled carrot, slightly moistened, 

 to the air at the temperature of the room. 



Bacillus megaterium, De Bary. Large rods 

 2 -5 ft wide, and four to six times as long. They 

 are usually somewhat curved. Transverse division 

 occurs, each segment attaining the length of the 

 original rod. In the fresh state they appear non-arti- 

 culated, but when treated with a dehydrating agent 

 (tincture of iodine, alcohol), they are seen to be 

 * Zopf, Die S^altpilze. 1885. 



