6 THE APODOUS HOLOTHURIANS 



Page 



Physiology 61 



Motion 61 



Digestion and Absorption 63 



Circulation and Nutrition G;> 



Respiration 64 



Excretion 64 



Sensation 64 



Regeneration 65 



Reproduction 66 



Ecology 66 



Taxology 68 



Key to the Subfamilies of Synaptidse 70 



Synaptinse 70 



Euapta 72 



Opheodesoma 73 



Polyplectana 76 



Synapta 78 



Synaptula 80 



Lcptosynapta 86 



Labidoplax 94 



Protankyra 97 



Anapta 109 



Dactylapta Ill 



Rhabdomolgus Ill 



Chiridotinse 112 



Chiridota 113 



Polycheira 120 



Tseniogyrus 121 



Trochodota 123 



Scoliodota 125 



Toxodora 125 



Achiridota 126 



Myriotrochinas 127 



Myriotrochus 127 



Trochoderma 129 



Acanthotrochus 130 



Concluding Remarks on the Synaptidse 130 



Interrelationships 130 



Geographical Distribution 131 



PART IV. THE MOLVADIID^E. 



Morphology 135 



Form and Size 135 



Color 136 



Body-surface 136 



Tentacles 137 



Sense-organs 138 



Nervous System 138 



Body-wall 139 



Epidermis 139 



Connective-tissue Layer 140 



