WORMS, MOSS-POLYPS, SPONGES, ETC. 117 
interesting mites whose life-history we are now 
prepared to read. 
Placed in the field of a microscope, these shells 
exhibit on their surfaces innumerable puncte or 
dots, which are in reality minute pores leading 
shrough the shell into the interior. Through these 
pores fhe animal substance that is contained within 
may be extended in the form of delicate processes, 
known as false feet (pseudopodia), by means of 
which the currents of food-particles may be di- 
rected to the organism. The bulk of the animal 
itself consists of a tiny bit of jelly-like substance, 
known as protoplasm, which shows none of the 
organs that are common to the higher animals; 
that is to say, there is neither mouth, stomach, 
heart, nor nerve. But despite these deficiencies the 
animal passes through the cycle of life with a free 
and satisfactory performance of the usual processes 
of assimilation, growth, and reproduction. There 
are few kinds Ae ele that are simpler in struc- 
ture than these so-called pore-bearers (Forami- 
nifera), and one of these is the almost universally 
distributed proteus-animalcule of our fresh waters 
(Ameeba), which differs only in the absence of a 
shell. 
The simplest form of foraminiferal shell is a 
hollow sphere, in which the protoplasm, or active 
animal substance, is lodged. In other forms this 
primitive sphere buds out into a number of addi- 
tional spheres, which gradually increase in size 
from the oldest to the newest, and may develop 
either one in advance of the other in a straight 
