CHAPTER II.

JANUARY.

Visit to the Ponds--Confervae--Spirogyra quinina--Vorticella--Common Rotifer--Three Divisions of Infusoria--Phytozoa--Protozoa--Rotifera--Tardigrada--Meaning of these Terms--Euglenae--Distinction between Animals and Vegetables--Description of Vorticellae--Dark-ground Illumination--Modes of producing it--The Nucleus of the Vorticella--Methods of Reproduction--Ciliated Protozoa--Wheel-bearers or Rotifers--Their Structure--The Common Rotifer--The young Rotifer seen inside the old one--an Internal Nursery--"Differentiation" and "Specialization"--Bisexuality of Rotifers--Their Zoological Position--Diversities in their Appearance--Structure of their Gizzard--Description of Rotifers