84. _Palæotherium_. (Lower Tertiary of Paris Basin) 190 85. _Hipparion_. (New World Pliocene) 192 86. Comparative series of Brains 194 87. Ideal section through all the above stages 195 88. Skulls of Canadian Stag, _Cervalces Americanus_, and Elk 198 89. Transmutations of _Planorbis_ 200 90. Transformation of _Strombus_ 202 91. Pigeons. Drawn from life 298 92. Pigeons (_continued_). Drawn from life 299 93. Fowls. Drawn from life 300 94. Fowls (_continued_). Drawn from life 301 95. Pair of Japanese Fowls, long-tailed breed 302 96. Canaries. Drawn from life 303 97. Sebastopol, or Frizzled Goose 304 98. The Dingo, or wild dog of Australia 304 99. Dogs. Drawn from life 305 100. Dogs (_continued_). Drawn from life 306 101. The Hairless Dog of Japan 307 102. The skull of a Bull-dog compared with that of a Deer-hound 307 103. Rabbits. Drawn from life 308 104. Horses. Drawn from life 309 105. Sheep. Drawn from life 310 106. Cattle. Drawn from life 311 107. Wild Boar contrasted with a modern Domesticated Pig 312 108. Seasonal changes of colour in Ptarmigan (_Lagopus mutus_) 317 109. _Oedicneus crepitans_, showing the instinctive attitude of concealment 320 110. Imitative forms and colours in insects 322 111. The larva of Puss Moth (_Cerura vinula_) 325 112. The larva of Puss Moth in disturbed attitude 326 113. Three cases of mimicry 328 114. Two further cases of mimicry; flies resembling a wasp in the one and a bee in the other 329 115. A case of mimicry where a non-venomous species of snake resembles a venomous one 330 116. A case of mimicry where a homopterous resembles a leaf-cutting ant 332 117. Feather-footed pigeon 359 118. _Raia radiata_ 368 119. Electric organ of the Skate 369