590 C. CLIFFORD DOBELL. 
tion occurs—two zygotes result, whereas in that only one is 
formed, 
The streaming of the granules observed so carefully by 
Schaudinn in B. biitschlii is due, I believe, merely to the 
fact that they have to travel to the poles of the cell to form 
the nucleus-like spore-rudiments. 
Why the last division should abort in the disporic forms, 
must remain an open question. A possible explanation is that 
it is a process correlated with the parasitic manner of life. 
When the organisms are removed from their host in the 
TEXT-FIG. C. 
% 
: 
“. 
ee 
Bacilli (sp. incert.) from rectum of Bufo vulgaris; sporulat- 
ing. x = a double individual. {Sublimate-alcohol, iron-alum 
hematoxylin; 2 mm. apochrom. x comp.-oc. 18. (x 2500). | 
feeces, they would soon—in all probability—be dried, and 
hence induced to enter the resting state. And for purposes 
of dissemination, it is obvious that two spores are always 
better than one, so that the last division—albeit abortive— 
would double the number of individuals capable of sporulat- 
ing. 
In my preparations of B. spirogyra were many other 
Bacteria,—amongst them a small Bacillus which was also 
sporulating. ‘lhe ordinary individuals formed a single ter- 
minal spore (text-fig. C) but here and there, double forms 
were to be found (x), which had spores placed at opposite 
poles. I find that similar forms have often been figured : for 
instance, Guilliermond (1908) gives several good examples 
