LIST OF ILLUSTRATIONS. 



XIX 



PAGE 



Wood-lice, . . 244 



Homarus vulgaris, . 247 



Spider-crab (Maid], 250 



Larva (Zoea) of Crab, 25 1 

 Morphology of Arach 



nida, ... 256 

 Pycnogonum littorale, Te- 



tranychus telarius, and 



Hydrachrta globulus, . 259 

 Scorpion, . . .261 



7heridion riparium, . 263 



Centipede, . . . 265 



Millipede, . . . 26b 



Diagram of Insect, . 268 

 Organs of the Mouth in 



Insects, . . .270 



Digestive system of Beetle, 272 

 Metamorphosis of the 



Magpie Moth, . . 275 



Bean Aphis, . . . 278 



Cockroach (Blatta), . 279 



Migratory Locust, . . 280 

 Aphis Lion, . . .281 

 Termites, . . .282 



Tipula oleracea, . . 284 



Pontia brassies, . . 285 



Cossus ligniperda, . . 286 



Tenthredo grossidarw, . 287 



Myrmica rufa, . . 289 



Stylops Spentii, . . 290 



Melolontha vulgaris, . 291 

 Cetonia aurata and Cur- 



culio sulcatus, . . 292 



Diagram of a Mollusc, . 293 



Flustra foliacea, . . 299 



Morphology of Polyzoa, 301 

 Flustra truncata, Val- 



keria, and Lophopus 



crystallinus, . . 33 

 Morphology of Tunicata, 307 

 Rhynchonella sulcata, . 312 

 Lingula anatina, . . 3 r 3 

 Terebratnla vitrea, . . 314 

 Cytherea chione, . . 3 21 

 Anatomy of My a ar en- 

 aria, .... 323 

 Shells of Lamellibranch- 



iata, . . . .3 2 5 

 Odontophore of the 



Whelk, . . -33 

 Diagrammatic section of 



a Whelk, . . . 33 1 



A mpullaria canaliculata, 332 

 Young of Eolis, and 

 adult Pteropod, . -333 



