ILLUSTEATIONS. XV 



135. Silver Fish (Lepiama saccharina) .... 260 



136. Edible Snail {Jldix povmtia) . . . . .262 



137. Two transverse series of teeth from radula of Limpet . . 264 



138. Shells of Lamellibranchs . . . . .264 



139. Common Calamary {Ldligo vulgaris) .... 265 



140. Water-snails (Lvmncddm) ..... 268 



141. Grey Field-slug (Zimaa; (M/restis) .... 270 



142. Testaoella (T. haliotidea) . . . . .271 



143. Garden Snail {Selix aspersa) ..... 272 



144. Structure of a Tunicate . ..... 278 



145. Development of a Tunicate ..... 279 



146. The Lancelet {Amphioxus lanceolatus) .... 279 



147. Diagrammatic Sections of an Invertebrate and Vertebrate . 281 



148. Skeleton of Horse . . . . . .286 



149. Lumbar Vertebra . . . . . .287 



150. Axis ........ 288 



151. Atlas . . ..... 288 



152. Skull of the Horse . . . . . .289 



153. Diagram of the Relations of the Principal Bones of the Mam- 



malian Skull . . . . . .290 



154. Fore and Hind Leg of Horse . . . . .292 



155. Pelvic Arch . . . . . . .295 



156. General View of the Intestines of the Horse . . . 298 



157. Diagram of Alimentary Canal ..... 299 



158. Theoretical, Longitudinal, and Median Section of Abdominal 



Cavity, to show Peritoneum .... 303 



159. Median Longitudinal Section of Head and Upper Part of Neck 



of Horse ....... 304 



160. Uro-Genital Apparatus of Male, with Arteries . . . 308 



161. Generative Organs of the Mare ..... 310 



162. Diagram of the Circulation of the Blood . . . 312 



163. Brain of Horse (dorsal view) ..... 316 



164. Brain of Horse (ventral view) ..... 317 



165. The Perch (Perca fiuviatUu) . . . . .322 



166. Diagram of the Circulation in Fishes .... 323 



167. Development of the Frog . . . . .326 



168. Male Crested Newt {Triton cristatus) .... 328 



169. Diagram of the Circulation in Beptiles .... 331 



