LIST OF ILLUSTRATIONS. 



xvn 



MOLLUSCS, CRUSTACEANS, AND ANNELIDA. 



Grey and Black Slugs . . 293 

 Fresh-water Snails . . . 294 

 Helix aspersa 295 



The Crayfish 297 



The Fresh-water Shrimp . 298 



INSECTS. 



Gyrinus natator (Whirli- 

 gigs) 301 



The Great Water- Beetle . 302 

 The Water-Boatman . . . 303 

 The Water-Bug .... 303 

 The Devil's Coach-Horse . 304 

 The Dor-Beetle .... 306 

 Pcederus riparhis .... 307 

 The Mario w Buzz .... 307 

 Odocantha melanusa . . . 307 

 Wing of Neuropterous In- 

 sect 309 



The Great Dragon-Fly . . 310 

 The Dragon-Fly or Horse- 

 Singer 311 



The Libellula puella . . . 312 



Pupa of the Dragon-Fly . 314 

 Different Forms of Caddis- 

 Cases with the Silk 



Grating 316 



Phryganea varia . . . . 318 



The Alder-Fly 319 



Per I a marginata . , . . 320 



The Yellow Sally . . . . 321 



Nemoura variegata . . . 322 

 (i) The Common Grass- 

 hopper and (2) The 

 Great Green Grass- 

 hopper 322 



Pupa (nymph) of Ephemera 



mdgata May fly . . 330 

 Ephemera danica . . 332, 333 

 Ephemera vulgata . 333, 334 

 Outline Eyes of Bae'tis, 



magnified 340 



Outline Eyes of Cloeon, 



magnified 341 



(i) Bae'tis with forewing 

 elongated at apex ; (2) 

 Cloeon with forewing 

 rounded at apex . . . 343 

 Bae'tis fluminum . . . . 345 



Bae'tis later alis 345 



The Red Ant 347 



The Saw-Fly 349 



The Governor 349 



The Water-Scorpion . . . 350 

 The Frog-Hopper . . . . 350 



The Sweet Flag . . . 

 Broad-leafed Pond- Weed 

 Yellow Water- Iris . 



FLOW 7 ERS. 



369 



374 

 377 



The Frog-BitFertile flower, 

 sterile flower, and leaf . 380 



The Club or Bull Rush . . 381 



Common Hornwort . . . 382 



Seed-vessel of Nuphar lutea 385 



The Common Reed . . . 388 



The Reed Mace .... 389 



