DEVELOPMENT OF THE BACTERIA. 115 
above all the hydrates of carbon and their deriv- 
atives; and in this respect they resemble animals.” 
Absorption. — How are these various substances 
absorbed? The observations of Grimm, Hoffmann, 
de Seynes, ete., permit us to assure ourselves that 
these organisms absorb by endosmosis the sub- 
stances upon which they are nourished. 
Grimm, upon examining with the microscope 
some particles of lemon containing bacteria and 
spores of alge, saw a certain number of the former 
gather around a spore, and fix themselves to it 
by one of their extremities. They did not pene- 
trate it; but when they abandoned it, the spore 
had diminished in volume, and lost a portion of its 
contents, while the bacteria had taken a greenish 
color. 
Hoffmann has seen that these little organisms, 
when placed in a solution of carmine or of fu- 
schine, after a time are colored an intense red, 
while the mucus surrounding them remains color- 
less. 
De Seynes, also, from his observations upon 
the vibrios which accompanied some colored fila- 
ments of Penicillium glaucum, believes that bacte- 
ria are susceptible of absorbing coloring matters 
from vegetables and from animals with which they 
are in contact. 
Oxygen. — The role of oxygen in the life of the 
bacteria has given rise to numerous controversies. 
First, it seems @ priori that the bacteria ought 
