DENDRONOTUS. 



cornea, enveloped in a general capsule (f. 10.) The optic nerves are very long; the 

 eyes are therefore removed to some distance from the large ganglions. The auditory 

 capsules contain numerous otolites of an elliptic form (f. 11, 12.) 



The generative organs do not appear to differ from those of Eolis, with the exception 

 that the ovarium, as before stated, lies above the central mass of the digestive system. 



EXPLANATION OF THE PLATE. 



Fig. 1. General view of the viscera of Dendronotus arbor escens : — a, buccal mass; b, oesophagus; 

 c, intestinal canal ; d, anns ; e, e, e, branches of the central mass passing into the 

 branchiae ; /, /, branches of the same passing into the tentacular sheaths ; g, ventricle 

 of the heart ; g ', auricle ; h, cerebral ganglions ; ti, olfactory ganglions ; i, i, portion of 

 the generative organs; j, ovarium. 



2. Digestive system: — a, buccal mass; b, oesophagus; c, stomach; d, intestine; e, duct 



connecting the alimentary canal with the liver ; /, /, /, branches of the central mass 

 passing into the branchiae ; g, g, branches from the same passing into the tentacular 

 sheaths ; h, h, central portion of the liver. 



3. A portion of the digestive system seen in profile, showing the duct connecting the liver 



with the stomach. The letters of this figure correspond to those of fig. 2. 



4. Buccal mass. 



5. Jaws deprived of their muscles. 



6. Tongue. 



7. A portion of the same more highly magnified. 



8. Dorsal view of the same. 



9. Cerebral ganglions showing the origin of the principal nerves : — a, ganglions of the 



dorsal tentacles (olfactory ganglions ;) b, b, the eyes. 



10. The eye more highly magnified. 



11. Auditory capsule with otolites. 



12. Otolites more highly magnified. 



