130 CG. CLIFFORD DOBELL. 
a flagellum (or bunch of flagella?) at either end. No simple 
nucleus, such as Kunstler and Gineste have described in 
Sp. periplaneticum, K. and G., can be made out; nor can a 
nuclear spiral, like that which saallonerebol abseaved in Sp. 
giganteum, be seen. The only contents which stain consist 
of a number of granules, which recall the figures of Sp. 
volutans given by Bitschli. In this case again I can 
merely say that these granules stain in a manner which 
causes me to believe that they are chromatin (see PI. 6, 
fio. 21a). 
Transverse division takes place in the manner usually seen 
in the Spirilla. It will not, therefore, be necessary to 
describe the process. I may say, however, that I have not 
been able to find any specimens in which an unequivocal 
division of the nuclear granules is taking place. 
Spore formation proceeds in the following manner. The 
nuclear granules, which in the vegetative stages are scattered 
throughout the cell, begin to aggregate at one end. A darkly 
staining, nucleus-like mass is thus produced (fig. 21b). A 
spore membrane appears round this, and, as it hardens, its 
staining capacity is gradually lost, so that finally an unstained, 
highly refringent spore becomes visible at the end of the 
organism (fig. 21c). Only a part of the granules enter into 
the formation of the spore. The remainder gradually dege- 
nerate, and are possibly in part volutine and other non- 
nuclear substances. Certainly a different intensity of colora- 
tion can often be noticed in the granules during even the 
vegetative stages of existence. Ultimately the.whole of the 
cell-remains without the spore break down, so that the single 
spore is left with more or less of the dead cell attached (fig. 
21d). Germination from the spore I have not observed. 
Spore formation has been described previously in several 
Spirilla, e.g. in Sp. sporiferum, Mig., and in Sp. endo- 
paragogicum, Sorokin. The details of the process are not 
known, however. Babés also found a Spirillam which 
sporulates, and he has figured it with deeply-stained masses 
at the ends during this process—resembling somewhat the 
