TABLE OF CONTENTS. 



DESCRIPTION OF PLATES. 



PAGE 



Plate I. Common Rat, Mus decumanus . - . . - . r . 2 6i 



II. Common Pigeon, Columba livia . . , , . , 7 4 . 265 



III. Common Frog, Rana temporaria . .. / : ^ . . 269 



IV. Skate, Raja batis\ heart, brain, Elasmobranch embryo . . 273 



V. Cellar Slug, Limax flavus s. variegatus . . -. . 281 



VI. Fresh-water Mussel, Anodonta cygnea . ' . . . . . 285 



VII. Lamellibranchiata : i, e. Ostrea edulis, its digestive tract, heart 

 of Area Noe, diagram of a left nephridium, Veliger of Car- 

 dium pygmaeum . . . . ." . . * 289 



VIII. Common Cockroach, Periplaneta orientalis . . . .. ,. 295 



IX. Arthropoda, i. e. Machilis polypoda, mouth-parts of Cidndela 

 littoralis, same of Apis mellifica, mouth-parts and ambulatory 

 limb of Scolopendra morsitans, Epeira fasciata, digestive 

 organs of Tegenaria domestica, Nauplius of Lepas fasci- 

 cularis . . . .- , * 299 



X. Common Crayfish, Astacus ftuviatilis, male-- . . . . 307 



,, XL Common Starfish, Asterias rubens , . , ...... . 311 



,, XII. Earthworm, Lumbricus terrestris . . . . .--. ,* ' . 315 



,, XIII. Medicinal Leech, Hirudo medidnalis . . ;. . . 319 



XIV. Cestoda, i;e. Tapeworm, unripe proglottis, uterus of ripe 



proglottis, proscolex, cystic Coenurus cerebralis . *. . 323 



Hydroidea, i. e. Hydra viridis, tentacle of Eucopella, sense-cell, 

 supporting-cell, cnidoblast, ganglion-cell of a guard polype of 

 Plumularia, two nematocysts of Millepora, one discharged, 

 the other not . . . . . . *. . . 326 



