hite
corpuscles in the blood of man and the animals bear a startling
resemblance to the _amoebae_ so far as regards size, general structure,
and movements, and are in fact known to Science as "amoeboids." The
white corpuscles change their shape, take in food in an intelligent
manner, and live a comparatively independent life, their movements
showing independent "thought" and "will."

Some of the amoebae (the diatoms, for instance) secrete solid matter
from the water, and build therefrom shells or houses, which serve to
protect them from their enemies. These shells are full of tiny holes,
through which the pseudopods are extended in their search for food, and
for purposes of movement. Some of these shells are composed of secreted
lime, and others of a flinty substance, the "selection" of these
substances from the ether mineral particles in the water, evidencing a
degree cf "thought," and mind, even in these lowly creatures. The
skeletons of these tiny creatures form vast deposits of chalk and
similar substances.

Next higher in the scale are the _Infusoria_. These creatures differ
from the amoebae inasmuch as instead of pseudopods, they have developed
tiny vibrating filaments, or thread-like appendages, which are used for
drawing in their prey and for moving about. These filaments are
permanent, and are not temporary like the pseudopods of the monera or
amoebae--they are the _first signs of permanent hands and feet_. These
creatures have also discovered the possibilities of organs and parts,
to a still greater degree than have their cousins the amoebae, and have
evolved something like a mouth-opening (very rudimentary) and also a
short gullet through which they pass their food and oxygen--_they have
developed the first signs of a throat, wind-pipe and food-passage_.

Next come the family of Sponges, the soft skeletons of which form the
useful article of everyday use. There are many forms who weave a home
of far more delicacy and beauty than their more familiar and homely
brothers. The sponge creature itself is a slimy, soft creature, which
fills in the spaces in its spongy skeleton. It is fastened to one spot,
and gathers in its food from the water around it (and oxygen as well),
by means of numerous whip-like filaments called _cilia_, which flash
through the water driving in the food and oxygen to the inner positions
of its body. The water thus drawn in, as well as the refuse from the
food, is then driven out in the