Activity of Charybdea 17 Temperature 17 Food and Feeding 18 Occurrence of Charybdea 18 AURELIA AND POLYCLONIA (_Cassiopœa_) 19 SUMMARY 22 DR. CONANT’S NOTES. CHARYBDEA. Light and Darkness 24 Sensory Clubs 26 Nerve 29 Side, Subumbrella 30 Pedalia, Velarium, Ganglia 31 Tentacles 32 Proboscis, Stomach, Phacelli 33 Temperature 33 Food and Feeding 33 Occurrence of Charybdea 33 Activity of Charybdea 34 AURELIA AND POLYCLONIA 35 CASSIOPŒA 39 AURELIA 39 HISTOLOGICAL. Method 40 Anatomy 41 Distal Complex Eye-- General 41 Cornea 42 The Lens 42 The Capsule 44 The Retina 45 (a) The Prism Cells 46 (b) The Pyramid Cells 48 (c) The Long Pigment Cells 50 (d) Subretinal Nerve Tissue 53 (e) Discussion of Literature 53 (f) Function of the Retinal Cells, Patten’s Theory, and further Literature 56 The Proximal Complex Eye 60 The Simple Eyes 61 Lithocyst and Concretion 63 The Epithelium of the Clubs 64