Xll CONTENTS. 



Tnpre 



Class Third — Cirripeda, . . . . 167 



Order I. — Pedunculata, . . . .168 



II. — Sessilia, . . . . 170 



Division III. — Articulata, 173 



Class Fifth. — Annclosa, .... 173 



Order I. — Sedentaria, 173 



II Antennata, . . . . 180 



III.— Apoda, 180 



On the Structure of the IMolIusca, . . . 181 



Class I. — Cephalopoda, 187 



Class II. — Pteropoda, 189 



Class III Gasteropoda, . . . .190 



Order I. — Gasteropoda Pulmonata, . 191 



II. — Gasteropoda Pectinibranchiata, . 193 



III. — Gasteropoda Tubulibranchiata, 196 



IV. — Gasteropoda Scutibranchiata, . 196 



V Gasteropoda Cyclobranchiata, 197 



VI — Gasteropoda Inferobranchiata, . 197 



VII. — Gasteropoda Tectibranchiata, 198 



VIII Gasteropoda Nudibranchiata, 199 



IX. — Gasteropoda Heteropoda, . 199 



X. — Gasteropoda Cirrobranchiata, . 199 



Class IV. — Acephala, or Lamellibranchiata, 200 



Class V. — Brachiopoda, 203 



Class VI Tdnicata, 204 



Explanation of the Figures, ..... 206 

 Directions for Collecting, Cleaning, and Arranging' 



Shells, 209 



Glossary of Terms used in Conchology, , . 221 



Index to the Classes, Orders, and Genera, . , 229 



