Ciliary Movement is the result of the presence on the surface of cells of minute, hair-like processes, called cilia. These are prolongations and specializations of the protoplasm. The cilia keep up a movement like that of a whip-lash, always in the same direction.

5. Reproduction is the multiplication of a cell, and may take place in one or two ways, either by direct division, amitosis, which is not the common method, or by indirect division, karyokinesis, karyomitosis, or mitosis. The latter is the more usual way.

In amitosis or direct division there is first noticed a slight contraction in the nucleus of the cell. This gradually goes on until two new nuclei are formed. During this period the cytoplasm begins dividing, and by the time the nuclei have migrated to opposite poles, separation has taken place and two new cells have formed.

If the cytoplasm fails to divide, multinuclear or giant cells may arise.