LIST OF ILLUSTRATIONS. 



PAGE 



Trilobites ...... 210 



[ Larvae of King Crab and Trilobite .210 



Brine Shrimp and Young . . .211 



Development of Lobster . . .211 



Crab . . .212 



Mysis ....... 213 



Penaeus ...... 214 



Nauplius of Penaeus . . . .215 



Zoe'a of Penaeus ..... 215 



Mysis-stage of Penaeus . . .216 

 Mussel ...... 220 



Snail ....... 221 



Slugs . , :. . . . . 221 



Chitons . ... . .222 



Pteropoda ...... 222 



Cuttlefishes ..... 223 



Development of Cockle and Ship- 

 worm ...... 223 



Teredo, or Ship-worm . . . 224 

 Dentalium and its Structure . . 224 

 Development of Dentalium . . 225 

 ,, Chiton (Loven) . 226 



Pond Snail, Gastrula-stage . . 226 

 Development of Trochus . . .227 

 Doris ....... 228 



228 



Bulla ....... 228 



Young of jEolis and Adult Pteropod 228 

 Larval, or Young Pteropod . .229 

 Brachiopoda and Development . . 229 

 Lob-worm (A renicola) . . .231 

 Nereis : a Marine Worm . . .231 

 Development of Worms . . .231 

 Serpula ...... 232 



Development of Frog . . . 235 

 Axolotl, showing the External Gills . 236 

 Newts . . . 238 

 Hippocampus, or Sea-horse . . 239 

 Amblystoma ..... 242 



Cecidomyia ..... 246 



Sitaris and its Development . . 247 

 Humming-bird ..... 249 



Swifts. . . . ' . . .250 



Sun-bird ...... 250 



Young Kangaroo . 254 



The Rosy Feather-star's Develop- 



ment ...... 256 



Chloeon ...... 257 



Metamorphosis or Swallow- tailed 



Butterfly . . . . .258 

 Cockroaches ..... 259 

 Dragon-fly and its Metamorphosis . 261 



