CONTENTS. XI 



CHAPTER XVL 



Ctenophora — General characters — Anatomy of Pleurobrachia — Divi- 

 sions of Ctenophora 130-134 



CHAPTER XVII. 



Distribution of Actiuozoa in space — Coral Reefs, their structure, and 

 mode of origin^Distribution of Actinozoa in time — Tabular view 

 of the divisions of the Zoantharia Sclerodermata and Rugosa, 134-140 



CHAPTER XVni. 



Annuloida — General characters of the Annuloida — General characters 

 of the Echinodermata — Development of the Echinodermata — 

 Divisions of Echinodermata, 141-144 



CHAPTER XIX. 



Echinoidea— General characters — Anatomy of Echinus — Divisions of 

 Echinoidea, 144-150 



CHAPTER XX. 



Asteroidea and Ophiuroidea — General characters of the Asteroidea — 

 Divisions of the Asteroidea^General cliaracters of tlie Ophiuroi- 

 dea — Families of the Ophiuroidea 150-155 



CHAPTER XXI. 



Crinoidea, Cystoidea, and Blastoidea — General characters of Crinoi- 

 dea— Of Cystoidea— Of Blastoidea, ISS-160 



CHAPTER XXII. 

 Holothuroidea — General characters — Families of Holothuroidea, i6o-i6z 



CHAPTER XXIII. 



Distribution of Echinodermata in space — Distribution of Echinoder- 

 mata in time — Crinoidea — Blastoidea — Cystoidea — Asteroidea — ■ 

 Ophiuroidea — Echinoidea — Holothuroidea, . . . 162-165 



CHAPTER XXIV. 



Scolecida — General characters of the class Scolecida — Entozoa — 

 Platyelmia — Tseniada — Stracture and development of the Tape- 

 worm— Hydatids, . . . . . . . . 165-171 



CHAPTER- XXV. 



Trematoda and Turbellaria — General characters of the Trematoda — 

 General characters of the Turbellaria — Planarida — Nemer- 

 tida, . . . 171-175 



