CONTENTS. XI 



PART IL—PALjEOZOOLOGY. 

 INVERTEBRATA. 



CHAPTER VIII. 



Zoological characters and chief divisions of the Protozoa — The palae- 

 ontological history of the Protozoa — The general characters of 

 the Foraminifera — Variations in the structure of the test in the 

 Foraminifera — The form of the Foraminiferal test and its varia- 

 tions — Distribution of the Foraminifera in space — Distribution 

 of the Foraminifera in time — Classification of the Foraminifera 

 — The general characters and distribution in time of the fami- 

 lies of the Foraminifera — Appendix on Eozoon Canadense, 109-143 



CHAPTER IX. 



The general zoological characters of the Radiolaria — The skeleton 

 of the Radiolarians and its chief variations as regards chemical 

 composition and form — Classification of the Radiolarians — Dis- 

 tribution of the Radiolarians in space — Distribution of the 

 Radiolarians in time — Literature of the Protozoa, . . 144-150 



CHAPTER X. 



General zoological characters of the Porifera — Canal -system of 

 Sponges — General structure of the skeleton and its variations in 

 Sponges — Distribution of Sponges in space — Different modes in 

 which the skeleton of Sponges may be preserved in the fossil 

 condition — General geological distribution of Sponges, . 151- 159 



CHAPTER XI. 



Classification of Sponges — Class Plethospongias — Order Myxospon- 

 gise — Ceratospongiae — Characters and geological distribution of 

 the Monactinellidae — Tetractinellidae — Lithistidae — Hexactinel- 

 lidae — Groups and geological distribution of Hexactinellids — 

 Octactinellidae — Heteractinellidae — Class Calcispongias — Homo- 

 ccela — Heteroccela — Syconidae — Leuconidae — Pharetrones — 

 Literature, 160-182 



CHAPTER XII. 



Groups of doubtful affinities — Archaeocyathinae — Archasocyathus — 

 Ethmophyllum — Pasceolus — Cyclocrinus — Nidulites — Litera- 

 ture, 183-189 



