26 ZOOLOGY. 
ber, measures about one fifth of an inch indiameter. Most 
of our native species are much more minute. The Eozoon, 
so-called, is supposed by some to be a Foraminifer, but 
others regard it as more probably inorganic, and simply a 
Fig. 16.—Actinospherium. a, amor- 
sel of food drawn into the cortical layer 
0; ¢c, central parenchymatous mass of 
the body ; d, some balls of food-stuff in 
the latter; e, pseudopodia of the cortical 
layer.—After Gegenbaur. 
Fig. 15.—B, Collosphera spi- 
nosa. with projecting conical 
points, containing little sphe- 
roids, which pass inte monad- 
like bodies C. ‘D, probably an 
early stage of C. A, a young Fig. 17.—Heliophrys variabdilis. A sun 
capsule of C. Hualeyi Miller.— animalcule, showing the pseudopods 
ter Cienkowski. nuclei, and vacuoles. —From Macallister, 
mineral. Undoubted Foraminifera occur in the Silurian 
formation, while large masses of carboniferous and cre- 
taceous rocks are formed by their shells. 
Order 2. Radiolaria.—These Rhizopods have the general 
structure of Amebsx, but secrete beautiful silicious shells, 
