82 MORPHOLOGY OF THE BACTERIA. 
Cells cylindrical, straight, rarely a little twisted, 
larger than the cells of B. termo, isolated or united 
in pairs, sometimes in fours, never more; length 
3.8 to 5.25 w, thickness attains 1.25 4; movements 
like those of B. termo, but a little more active. 
Is found in various vegetable and animal in- 
fusions of fresh or salt water, often takes the 
form of zooglea containing motionless rods in 
their mucus substance. Warming has met it 
in the form of chains composed of eight to ten 
cells (torw/a). Its protoplasm is dotted with re- 
fractive granules. 
It is not known whether B. lineola constitutes 
a specific ferment (Cohn). 
The B. fusiform, Warming, differs from the preceding by 
the form of its body, which is attenuated at the two extrem- 
ities; length 2 to 5 wp, width 0.5 to 0.8 4; plasma not punc- 
tated. 
Beside these species, which have been well 
studied, may be placed the following, which 
demand new investigations : — 
B. punctum, Ehrb. 
Elongated rods, oval, colorless, having slow 
movements, oscillating, often united in pairs; 
length 5.2 pw, thickness 1.7 ». Diverse infusions 
of animal substances. 
B. catenula, Duj. 
Body filiform, cylindrical, often united in 
three, four, or five; length 3 to 4 p, thickness 
0.4 to 0.5 w. In fetid infusions, in typhoid fe- 
ver (Coze and Feltz). 
