CONTENTS 



CHAP. I. PEOTOZOA 



The Cell 1 

 Amoeba 



Paramecium ... 9 



Vorticella . . .13 



Cercomonas . . .16 



General Considerations . 17 



Morphology . . 17 



Physiology . . .19 



Psychology . . .21 



Reproduction . . 22 



Distribution . . 23 



Symbiosis ... 24 



Parasitic Protozoa . . 24 



Opalina ... 24 



Monocystis ... 25 



Plasmodium . . 25 



Trypanosoma . . 28 



CHAP. II. COELENTERATA 



Hydra .... 30 



Structure ... 31 



Eeproduction . . 36 



Obelia .... 39 



Hydroid ... 40 



Medusoid ... 42 

 CHAP. III. PLATYHELMIA 



Distoma ... 45 



Structure ... 46 



Life-history . . 49 



Taenia .... 51 



Structure ... 52 



Life-history ... 56 



General Considerations . 58 

 Primary and Secondary 



Body Cavities . . 58 



Trochozoa . ' ' ._ 60 

 CHAP. IV. MOLLUSCA 



Anodonta ... 61 



External Morphology . 62 



Pearls 63 



PAGE 



Internal Morphology . 65 



Alimentary Canal . 65 



Coelom and Kidneys 67 



Vascular System . 68 



Nervous System . 70 



Reproductive Organs 71 



Development . . 71 



General Considerations . 71 



Trochophore Larva . 73 



CHAP. V. ANNELIDA 



Lumbricus . . .76 



External Morphology . 77 



Internal Morphology . 78 



Alimentary Canal . 78 



Body Cavity . . 81 



Vascular System . 82 



Excretory Organs . 83 



Nervous System . 84 



Reproductive Organs. 84 



Development . . 86 



Nereis .... 

 General Considerations 

 Trochophore Larva 



CHAP. VI. CRUSTACEA 



Nephrops 



External Morphology 

 Segments and Appen 



Gills 



Internal Morphology 

 Integument and Skele 



ton 



Muscular System 

 Alimentary Canal 

 Circulatory System 

 Body Cavity 

 Nervous System 

 Excretory Organs 



89 

 89 

 89 



91 

 92 



92 

 98 

 99 



99 

 100 

 100 

 103 

 105 

 106 

 108 



