103 



Fig. 55. Left branchial heart, showing the branchial 

 appendage or pericardial gland. From ventral 

 surface. x 1. 



Fig. 56. Distal portion of lateral vena cava, showing 

 two semi-lunar valves at entrance to branchial 

 heart, and also apertures leading- into venous 

 appendages, and into the network of vessels 

 occurring in the spongy wall of the branchial 

 heart. x 1. 



Fig. 57. Mantle cut down ventral median line, and 

 opened out flat. The left half is seen from 

 the dorsal surface, after removing the skin. 

 J/. V. and M, I'j represent the two main 

 pallia! veins. x i. 



Fig. 58. Portion of arm, showing relation of main veins 

 to the network which drains the arm. x |. 



Plate VIII. 



Fig. 31. Ventral view of ink sac, after removal of 

 epithelium covering visceral sac, showing 

 visceral nerves, and nerve artery and vein of 

 ink sac. x |. 



Fig. o2. Ventral view of ink sac, showing veins and 

 arteries injected. The visceral and iridescent 

 envelopes cut open and turned back. x 1. 



Heart from ventral surface, showing paired 

 coronary veins. x 1. 



(jill leaflet, showing network of arteries 

 flowing into the main axial vessel which leads 

 into the efferent artery. x 1. 



Portion of gill filament from external surface, 

 showing terminations of venous vessels of the 

 second order. x 1. 



Fig. 63. Portion of gill, from inner surface, showing 

 main arteries and veins injected — second inner 

 filament cut away. Much enlarged. 



Pdght statocyst, from ventral surface. x 3. 



Statolith, from free surface. Much enlarged. 



Auditory capsules opened to show the statocyst 

 attached to capsule by vascular network, x 1. 



