xvi CONTENTS 



II. BODY CONSISTING OF A SINGLE CELL. 



PAGE 



VIII. Phylum : Protozoa ... 479 



(a) SHAPE CONSTANT ; SURFACE ENTIRELY OR PARTIALLY CILIATED ; WITH 

 DEFINITE MOUTH AND ANUS. 



CLASS I.: INFUSORIA ... ... ... ... ... ... ... 479 



(b) SHAPE CONSTANT ; WITH ONE OR A FEW LONG FLAGELLA IN PLACE 

 OF CILIA. 



CLASS II. : FLAGELLATA ... ... ... ... ... ... ... 482 



(c) NAKED, OR FURNISHED WITH SHELLS OR SKELETONS; WITHOUT 



DEFINITE MOUTH OR ANAL OPENING. 



CLASS III.: EHIZOPODA ... ... ... ... ... ... ... 483 



THE GEOGRAPHICAL DISTRIBUTION OF ANIMALS ... 485 



NOTE. It must not be supposed that the above synopsis includes the whole of the 

 Animal Kingdom. There are many groups and peculiar forms which do not belong 

 to any of the orders here named. Among them are the Sirenia, the Dipnoi, 

 Balanoglossus and the Ascidians, the Eotifera, the Polyzoa, and Peripatus. These 

 animals for the most part occupy less important positions in Nature, but in science their 

 characters and relations are of the greatest importance. The study of these forms can 

 most profitably be commenced when a sound knowledge of those considered in the 

 present text-book has been acquired. 



