4 E. KLEIN. 
within recent years almost constantly observed a similar change 
in early phases of the growth of anthrax bacilli in gelatine 
plates (beef bouillon; gelatine 10 per cent.; peptone 1 per 
cent.; salt 1 per cent.). Already in very early phases, when 
the colonies are only just visible as angular greyish spots, and 
_when by their numerous outgrowing filamentous prolongations 
they become more and more connected with one another—that 
is, between twenty-four to forty-eight or seventy-two hours’ in- 
cubation at 20° C.—numbers of these filamentous sproutings, 
examined in impression cover-glass specimens, are seen to be 
made up entirely or partially, not of the typical filaments com- 
posed of the cylindrical typical bacilli, but of large spindle- 
shaped spherical or oval elements, the protoplasm of which 
showing abundant vacuolation. In figs. 2 and 3 such growing 
outrunners of young colonies are accurately represented by pho- 
tograms. There can be no question, then, of these forms being 
indicative of active growth ; as a matter of fact, later on—that 
is after four days and more, as growth proceeds and liquefac- 
tion becomes pronounced—such forms do not obtain any more ; 
the threads are all uniformly made up of the typical cylindrical 
bacilli. 
When comparing the colonies of the thrush fungus, Sac- 
charomyces mycoderma, or Oidium albicans, growing 
on gelatine plates, it will be found that the impression pre- 
parations obtained therefrom show in many filaments the very 
identical appearances ; and that while some threads or parts of 
threads are composed of cylindrical cells, others are made up 
of oval, spindle-shaped, and spherical cells; the same local 
accumulation of the growing protoplasm as huge spindles or 
spheres, and the same vacuolation of the protoplasm are ob- 
served in both. I conclude from this that, although the 
Bacillus anthracis is a typical bacillus in the blood of 
animals infected with, or dead from, anthrax, and also in most 
conditions of artificial cultivation, it nevertheless under certain 
conditions (early stages of growing colonies on gelatine) 
assumes a character by which it closely resembles a Sac- 
charomyces mycoderma, or perhaps Oidium, and thereby 
