ELUCIDATIONS. 
it is scarcely possible by any figure to express the genuine 
-haMt^ of the animal, especially when arrivetj at its full 
growth, when the branchings are extremely numerous. 
It may be added that two or three distinct species of this 
kind of compound VorticellaB exist, which are all evidently 
confounded by Linnaeus and some others under the name 
of Vorticella anastatica. Their general mode of growth 
^6r increase is as follows : viz. the first or parent animal 
swims single, and is furnished Avith an extremely short 
*"stem, hardly equalling the length of the body ; blit 
A^hich, in a few hours, extends to a surprising degree, 
and becbmes the chief or general stem ; after this the 
body divides longitudinally, forming two distinct and 
'similar bodies, whose respective stems very soon begin to 
lengthen, and, after some hours, each of these two bodies 
again divides, forming double the former number. This 
method of increase is continued till all the numerous 
’^ranches of the animal tree are formed ; and w^hen it has 
— rrc: - 
thus remained for the space of eight, ten, or even many 
more days, the several animals separate, in succession, 
from their respective branches or stems, and swim about in 
order to form new colonies ; so that in the space of some 
days the tree is left perfectly bare. To this, which is the 
'general mode of increase, the accurate Muller has added 
still ’litore surprising one, viz. that the naked stems again 
^epullulate, producing new heads or bodies in place of 
ffeose which have departed. This latter mode of increase, 
I must confess, has never yet fallen under my OAvn ob- 
