LIST OF ILLUSTRATIONS xvil 



PAGE 



Fig. 66. A Cell of the Nervous Reticulum of a Coelen- 



terate 203 



Fig. 67. Side View of the Body of the Ctenophore, 



Pleurobrachia 213 



Fig. 68. An Epithelio-Muscle Cell (" Neuro-Muscle 



Cell") oi Hydra 238 



Fig. 69. Diagram of Simple Multicellular Arcs ... 239 

 Fig. 70. Diagrammatic Dorsal View of the Upper End 



of the Spinal Cord of Larval Amblystoma . 253 



