CONTENTS xiii 



PAGE 



The brain . . . 71 



Reproduction 72 



The phyla of the animal kingdom 74 



Tabular view of the phyla 75 



SECTION III 



PHYLUM PORIFERA 76 



Example of the Phylum and Class Sycon gelatinosum . 76 



SECTION IV 



PHYLUM CCELENTERATA 90 



Class i. The Hydrozoa .91 



Example of the Class Obelia . . . . 91 



Class 2. The Scyphozoa 108 



Example of the Class Aurelia aurita .... 108 

 Class 3. The Actinozoa 1 14 



Example of the Class Tealia crassicornis . . .114 

 Class 4. The Ctenophora 125 



Example of the Class Hormiphora plumosa . . .125 



SECTION V 



PHYLUM PLATYHELMINTHES 129 



Class i. The Trematoda 129 



Example of the Class Distomum hepaticum . . .129 

 Class 2. The Turbellaria 137 



Example of the Class Planaria torva . . . .138 

 Class 3. The Cestoda 138 



Example of the Class Tania solium . . . .138 

 Class 4. The Nemertinea 145 



Example of the Class Tetrastemma .... 145 



SECTION VI 



PHYLUM NEMATHELMINTHES 149 



Class. The Nematoda 149 



Example of the Class Ascaris lumbricoides . . . 149 



