268 FIRST FORMS OF VEGETATION. : 
not bring any of our preconceived notions of vege- 
table forms and structures, for we shall assuredly 
find them completely overthrown, by the new and 
strange modes of organization which these minute 
plants display. Indeed, so peculiar and abnormal 
are some of these modes, so unlike those of all 
other plants, that the zoologist and botanist are not 
yet fully agreed as to which kingdom of nature— 
the animal or the vegetable—they ought to be re- 
ferred ; and, accordingly, they have occasionally 
been classed and figured as plants by one natur- 
alist, and as animals by another. Ehrenberg, the 
great Prussian naturalist, whose microscopic re- 
searches have laid open to us a new and strange 
world of minute organic existence, and to whose 
untiring industry and patience we are indebted 
for the discovery of most of the wonderful atomies 
under consideration, was from the very first firmly 
convinced of their animal nature; and the credit 
attached in this country to his notions, had the 
effect of turning away the attention of botanists 
from them; while the zoologists rejected them 
from their systems as suspicious and anomalous 
objects; and the mere microscopist regarded 
them simply as new and strange forms of life, 
with the contemplation of whose beautiful struc- 
ture he could agreeably while away a leisure hour. 
In external form the diatoms present remarkable 
