82 THE OCEAN WORLD. 
this little creature was thought to be a polyzoon; but d’Orbigny, 
in his “ Prodrome de Paléontologie,” has correctly placed it among 
the Foraminifera, thinking that it 
appeared to occupy a place be- 
tween the two classes. 
Our exact knowledge of the 
Foraminifera is of comparatively 
recent date. Great numbers of 
minute particles, of regular and 
symmetrical form, were long dis- 
tinguished as existing on the 
sands of the sea-shore. These 
early attracted the attention of 
Fig. 14.—Fabularia discolithes (Defrance), observers. But with the dis- 
natural size and magnified. covery of the microscope, these 
small elegant shells, which were 
among the curiosities revealed by the instrument, assumed immense 
importance. Linnzeus placed them with the beautiful genus Mawutilus 
as a group, which would include, according to that author, all the 
multilocular shells. In 1804 Lamarck also classed them among 
Fig. 15.—Alveolina ovoidea (d’Orbigny), Fig. 16.—Dactylopora cylindracea (Lamarck), 
natural size and magnified. natural size and magnified. 
the molluscous cephalopods. But Alcide d’Orbigny, who had devoted 
long years to their study and observation, and may be considered 
the great historian of the Foraminifera, showed that this method 
of classification was inexact. Dujardin separated them altogether 
from the class of molluscs, and showed that they ought to be con- 
signed to a much lower class of animals. 
We have stated that the Foraminifera are of microscopic dimen- 
sions. With some trifling exceptions, this is generally true; but 
