LIST OF ILLUSTRATIONS. 



FIG. PAGB 



KENTISH PLOVEK WITH EGGS AND YOUNG Frontispiece 



1. SPIRACLES AND AIH-TTJBES OF COCKROACH .. .. .. 3 



2. GILLS OF MUSSEL . . . . . . . . . . 4 



3. A CELL GREATLY MAGNIFIED . . 11 



4. AM<EBA . . . . . . . . . . . . 12 



5. EGG-CELL AND SPERM-CELL . . . . . . 13 



6. DIAGRAM OF CIRCULATION .... 23 



7. PROTOZOA . . . . . . . . . . 38 



8. HYDRA VIRIDES . . . . . . . . . . 43 



9. AURELIA : LIFE-CYCLE . . . . . . . . 45 



10. LITER-FLUKE EMBRYONIC STAGES ;. . . . . 47 



11. DIAGRAM OF DEVELOPMENT .. .. .. .. ..51 



12. WING OF BAT (PIPISTRELLE) .... . . . . 64 



13. VARIATIONS OF THE NOCTULE ..' .. .. ..67 



14. LONG-EARED BAT . . . . . . 68 



15. PIPISTRELLE .. .. .. ..69 



16. WHISKERED BAT . . . . . . 70 



17. VARIATIONS ADJUSTED TO THE STANDARD OF THE NOCTULE . . 73 



18. CATERPILLAR OF A MOTH ON AN OAK SPRAY .. .. 85 



19. LOCUST RESEMBLING A LEAF . . . . . . . . 86 



20. MIMICRY OF BEES BY FLIES . . . . . . . . 91 



21. EGG AND HEN .. .. .. .. 141 



22. STAG-BEETLES .. .. .. .. .. .. 180 



23. TACTILE CORPUSCULES . . . . . . . . . . 247 



24. TOUCH-HAIR OF INSECT . . . . . . . . . . 248 



25. TASTE-BUDS OF RABBIT . . . . . . . . . . 250 



26. ANTENNULE OF CRAYFISH . . . . . . . . 259 



27. DIAGRAM OF EAR . . . . . . . . . . . . 263 



28. TAIL OF MYSIS . . . . . . . . . . 266 



29. LEG OF GRASSHOPPER . . . . . . . . . . 266 



30. DIAGRAM OF SEMICIRCULAR CANALS 270 



