COMPARATIVE ANATOMY 



PAGE 



C. LAMELLIBRANCHIA ....... 61 



D. CEPHALOPODA ....... 67 



^ T . ARRANGEMENT OF THE ORGANS IN THE MANTLE CAVITY, AND 



OF THE OUTLETS OF INNER ORGANS IN THAT CAVITY . 71 



A. GASTROPODA ... .71 



B. SCAPHOPODA ....... 80 



C. LAMELLIBRANCHIA ....... 81 



D. CEPHALOPODA ... ... 81 



VI. THE RESPIRATORY ORGANS . . . 84 



THE TRUE GILLS OR CTENIDIA ... .84 



A. AMPHINEURA .... .86 



B. GASTROPODA .... .88 



C. LAMELLIBRANCHIA ... . .91 



D. CEPHALOPODA ... .96 

 ADAPTIVE GILLS . . . 97 

 LTTNGS ..... 99 



VII. THE HYPOBRANCHIAL GLAND . 101 



VIII. THE HEAD . 101 



A. GASTROPODA . . . . . . .102 



B. SCAPHOPODA . ... 104 



C. CEPHALOPODA ..... . 105 



IX. THE ORAL LOBES OF THE LAMELLIBRANCHIA . . 105 



X. THE FOOT AND THE PEDAL GLANDS . 106 



A. AMPHINEURA ... . . 106 



B. GASTROPODA . . . 107 



C. SCAPHOPODA ... . .112 



D. LAMELLIBRANCHIA .... . 112 



E. CEPHALOPODA .... . 115 



XI. SWELLING OF THE FOOT (Turcjescencc] .... 118 



XII. MUSCULATURE AND ENDOSKELETON . 119 



A. AMPHINEURA ..... .120 



B. GASTROPODA . . . . . . .120 



C. SCAPHOPODA . . . . . . .123 



D. LAMELLIBRANCHIA . . . . . .124 



E. CEPHALOPODA ... . 126 



XIII. THE NERVOUS SYSTEM . . 128 



A. AMPHINEURA ..... 128 



B. GASTROPODA . 132 



