XI 1 



LIST OF ILLUSTRATIONS 



Page 



Poison Spines of Fishes (after Giinther) - 356 

 Sting of Bee (after Carlet) - - 358 



Poison-Spine of a Sea-Urchin (Astheno- 



soma urens) (after P. and F. Sarasin) - 361 

 Baboons retreating from Wild Dogs (from 



Brehm) 364 



THE CHAMOIS (Riipicapra Tragus) - 366 

 The Common Squirrel (Sciurus vulgaris) - 368 

 The Dodo (Didus ineptus] - - 369 



Slug suspended by a Thread of hardened 



Slime - - - 374 



Front Part of Chick Embryo - - - 381 

 Californian Hag-Fish (Bdellosloma) - - 383 

 Diagram of Circulatory System in a Fish - 384 

 Diagram showing the Gill-Pouches of a 



Lamprey (Petromyzon) - - - - 384 

 Circulatory and Breathing Organs of Hag 



(Myxine glntinosa) (after J. Miiller) - 385 

 Horizontal Section through a Shark, show- 

 ing the Gill-Pouches) (after Gegenbaur) 386 

 The Sea-Cat (Chimara monstrosd) (after 



Garman) 387 



Horizontal Section through the Breathing 



Organs of a Teleost (after Gegenbaur) - 388 

 Lancelet (Amphioxus lanceolatus) (after 



Boveri) 389 



Section through an Acorn-headed Worm 



(Balanoglossus) (after Spengel) - - 390 

 Mail-Shell (Chiton] - ... 392 



Dissection of a Cuttle-Fish (Sepia) to show 



Gills (after Savigny) - ... 392 

 Ormer (Haliotis) dissected to show Gills - 394 

 Shells of various Sea-Snails (after Lang) - 394 

 Diagram of a Whelk (J5ucftnufft)(a.ftct Lang) 395 

 Gill-Cavities of John Knox's Limpet and 



Common Limpet 396 



Diagram of Sea- Hare (Aplysid) (after Lang) 396 

 Diagrammatic Cross Section of Hind- 



gilled Snail 396 



Sea- Lemon (Doris) (after Alder and Han- 

 cock) - .... 397 

 Freshwater Mussel (Anodonta) opened to 



show Gills 398 



Freshwater Mussel (Anodonta) imbedded 



in mud 398 



Gills of Lobster (Homarus vulgaris)- - 401 

 Gills of a Crab (after Gegenbaur) - - 404 

 Gills of Mantis-Shrimp and Sand-Hopper 



(after Milne-Edwards and Sars) - - 404 

 Mud-Shrimp (Nebalia) (after Milne-Edwards) 405 

 A Mussel-Shrimp (Cypris), enlarged - 406 

 King-Crab (Limulus) (partly after Ray 



Lankester) 406 



Scale- Worm (PolynoS) (after Milne-Edwards) 408 

 Lugworm (Arenicola piscatoruni)^ showing 



Gills 409 



A Tube-Worm (Terebella), showing Gill- 

 plumes on Head 409 



Page 



Priapulus (after Ehlers) .... 4 IO 

 Mouth-Area of a Sea-Urchin (Echinus 



esculentus) (from Kiikenthal)- - - 412 

 Cross Section through Arm of Star-Fish 



(from Kiikenthal) - - - - 413 



Heart-Urchin (Spatangus purpureus) 415 

 Dissection of Sea-Cucumber (after Ludwig, 



simplified) 416 



Diagrammatic Vertical Section of a Sea- 

 Anemone 417 



Swim-Bladder of Bichir (Polypterus), dia- 

 grammatic - - - - - - 421 



Sections through Lungs, showing Ingrowth 

 of Folds (after Boas) .... 424 



Head of Crocodile to show Breathing 



Arrangements (after Boas) - - - 425 

 Lungs of a Chameleon (after Wiedersheim) 425 

 Lungs and Air- Sacs of a Bird (after Heider) 426 

 Convoluted Windpipe of a Crane - - 427 

 Air- Passages of Lungs of Man - - - 428 

 Mouth, Nose, &c., of Man, in Section - 429 

 Lung of Land-Snail (Helix) (after Hatschek 



and Cori) 433 



Breathing Organs of Shield-bearing Centi- 

 pede (Scutigera) (after Haase) - - 436 

 Air-Tubes of Cockroach (Periplaneta ori- 



entalis) (after Hatschek and Cori) - - 438 

 Dissection of Honey-Bee (Apis mellifica] 



(after Leuckart) 439 



The Drone-Fly (Eristalis tenax) and its 



Larva, the Rat-tailed Maggot - - 441 

 Larva and Pupa of Common Gnat (Culex 



pipiens), enlarged .... 442 

 Mygale (partly dissected) from below - 443 

 THE MUD-SKIPPER (Periophthalmus Koel- 



reuleri) 448 



Roach (Leuciscus rutilus) and Bleak 



(Alburnus lucidus) - ... 449 

 Indian Snake-headed Fish (Ophiocephalus) 451 

 Climbing Perch (Anabas scandens) - - 452 

 Dissection of a Bitterling (Rhodeus amarus) 452 

 Roof of Gill-Cavity in a Species of Peri- 

 winkle (Littorina rudis) (after Pelseneer) 460 

 Apple-Snail (Ampullaria) (after Semper) - 461 

 A Stone - Fly (Pteronarcys} (after New- 

 port) - - - 464 

 Air-Tubes of Rectal Gills in Dragon-Fly 



Nymph (after Oustalet) - - - 465 

 Nymph of Common May- Fly - - - 465 

 Hinder Part of Nymph of a May -Fly 



(Cloeon dipterum) (after Zimmermann) - 465 

 Crustacean - like Nymph of a May -Fly 



(Prosopistoma) (after Vayssiere) - - 466 

 Stages in Life-History of a Sand-Midge 



(Simulia) (after Verdat) - . 468 



Diagrammatic Cross Section through 

 Breathing Organs of Robber Crab 

 (Birgus latro) (after Semper) - - 469 



