INFUSORIA. 
17 
CHATTER II. 
Infusoria, 
Continued. 
I ms brief sketch of the history of the Vorticelln will serve 
to illustrate that of the whole class of Infusoria j as the 
facts, at least the earlier ones, with slight modifica- 
tions, are common to all. The round bodies resem- 
bling beads, which we mentioned as scattered in the 
interior of the bell, are characteristic of the whole of 
these animals. Professor Ehrcuberg considers them to 
be so many stomachs, connected either with the com- 
mon mouth, or with an intestinal canal which runs 
through the body. To this conclusion he came by pro- 
secuting a series of curious and ingenious experiments. 
By mixing coloured substances, such as carmine or indigo, 
with the water in which the animalcules were living, he 
found that they readily imbibed them, and that the 
colouring matter was presently accumulated in these in- 
ternal vesicles, which then appeared crimson or blue, 
accoidiug to the pigment employed. Hence he appdied 
the name Polyga&trica to the class, a term which would be 
as appropriate as it is significant were it quite certain 
that his conclusions legitimately follow from his premises, 
ut later naturalists have doubted that these vesicles are 
B 
