EXPLANATION OF THE FIGURES. Vll 



FIG. 



20. Tympanum and small bones of the ear, twice the natural size ; c, tym- 



panum ; m, malleus ; n, incus ; o, orbiculare ; s, stapes. 



21. Section of the brain of a crow, showing- the origin of the nerves of the 



special senses. 



22. Diagram of the larynx, in man. 



23. Larynx of the merganser (Mergus merganser} . 



24. Nests of Ploceus Philippinus, male and female. 



25. Distribution of nerves to the muscular fibres. 



26. Test, or crust-like covering of an Echinoderm ( Cidaris) . 



27. Muscular ribbons of the willow-moth ( Cossus ligniperda). 



28. Vertebra of a cod-fish. 



29. Disposition of the muscles of the trout (Salmo tnitta}. 



30. Disposition of the muscles of an owl (Strix brachyotis). 



31. Jelly-fishes (Stomobrachium crudatum, Hippocrene BougainviUii). 



32. Leech, showing the terminal cups. 



33. Portion of a Nereis, showing the gills as organs of motion. 

 34 - 43. Modifications of the fore-arm. 



34. Monkey. 35. Deer. 36. Tiger. 37. Whale. 38. Bat. 

 39. Pigeon. 40. Turtle. 41. Sloth. 42. Mole. 43. Whale. 



44. Leg of a beetle. 



45. Leg of a lizard. 



46. Skeleton of a tiger. 



47. Cuttle-fish (Loligo ittecebrosa}. 



48. Sea-anemone (Actinia marginata) ', a, mouth ; , stomach ; c, general 



cavity of the body. 



49. Planaria, showing the mouth, stomach, and its branches. 



50. Jaws, stomach, and intestine of a sea-urchin (Echinus lividus). 



51. Plan of the digestive organs of an Insect. 



52. Plan of the digestive organs of a land-slug ( TebennopJionis Caroliniensis) . 



53. Globules of chyle. 



54. Portion of intestine, showing the lacteals of man, and their entrance 



into a vein. 



55. Jaws of an Echinoderm (Echinarachnius parma). 



56. Jaws of a sea-urchin (Echinus granulatus). 



57. Beak of a cuttle-fish. 



58. Portion of the tongue of a Mollusk (Natica keros), magnified. 



59. Jaws of an Annelide (Nereis). 



60. Trophi (organs for taking food) of a beetle. 



61. " of a bee. 



62. 63. " of a squash-bug. 



64. " of a butterfly. 



65. " of a Rotifer (Brachionus). 



66. Jaws of ditto, magnified. 



