BACILLUS ANTHRACIS. 549 
preparations they are seen to be composed of a series of 
rectangular, deeply stained segments. When obtained 
directly from the blood of an infected animal the free 
ends of the rods are slightly rounded, but those com- 
ing in contact with one another are quite square. In 
cultures the ends are seen to be a trifle thicker than 
the body of the cell and somewhat concave, giving the 
appearance of joints of bamboo. At one time much stress 
Anthrax bacillus. >< 900 diameters. Agar culture. 
was laid upon these peculiarities as distinguishing marks 
of the anthrax bacillus; but it has been found that these 
are the effects of artificial cultivation and not necessarily 
characteristic of the organism under all conditions. An- 
other peculiarity of this bacillus is that it is enclosed 
in a transparent envelope or capsule, which in stained 
preparations may be distinguished by its taking on a 
lighter stain than the deeply stained rods which it sur- 
rounds. 
