CONTENTS. XI 



CHAPTER XII. 



Characters of the Crinoidea General structure of a Crinoid Structure 

 of the column of the Crinoids Structure of the calyx Distribu- 

 tion of the Crinoids in time Crinoidea articulata and tesselata 

 Characters of the Cystoidea Structure of the column, calyx, 

 and appendages of the Cystideans Pectinated rhombs Distribu- 

 tion of the Cystideans in time Chief genera of Cystoidea Cha- 

 racters of the Blastoidea Structure of Pentremites Distribution 

 of Blastoidea in time Characters and distribution in time of the 

 Holothuroidea, 118-135 



CHAPTER XIII. 



Characters of the Annulosa Characters of the Annelida Characters 

 of the Tubicola Distribution of the Tubicola in time Cornulites 

 Conchicolites Serpulites Trachyderma Spirorbis Serpula 

 Ditrupa Characters of the Errant Annelides Scolithus 

 Arenicolites Tracks of Errant Annelides, .... 136-143 



CHAPTER XIV. 



Characters of Arthropoda Distribution of Arthropoda in time Cha- 

 racters of Crustacea Morphology of a typical Crustacean General 

 facts as to the past existence of Crustacea Table of the divisions 

 of the Crustacea Characters and divisions of the Cirripedia 

 Structure of the shell in the Balanidse Distribution of the Balan- 

 idae in time Characters and distribution of the Verrucidse Struc- 

 ture of the Pedunculated Cirripedes Distribution of the Lepadidse 

 in time, . 143- 1 55 



CHAPTER XV. 



Characters and orders of the Entomostracous Crustaceans Ostracoda 

 Distribution of the Ostracoda in time Estheria Characters 

 and distribution in time of the Phyllopoda Characters of the 

 Trilobita General structure of a Trilobite Appendages of Tri- 

 lobites Systematic position of Trilobites Distribution of Trilo- 

 bites in past time Leading families of the Trilobita Characters 

 and divisions of the Merostomata Characters and distribution in 

 time of the Eurypterida Characters and distribution in time of 

 the Xiphosura, I 55' I 75 



CHAPTER XVI. 



Characters of the Malacostrata Characters of the Edriophthalmata 

 Characters and distribution in time of the Amphipoda Cha- 

 racters and distribution in time of the Isopoda Characters of the 

 Podophthalmata Characters and distribution of the Stomapoda 

 Characters and distribution of the Decapoda Macrura Ano- 



-Brachyura, ........ 175-180 



CHAPTER XVII. 



Characters of the Arachnida General distribution of the Arachnida in 

 time Characters and distribution of the Scorpionidse Characters 



