3o6 CLASSIFIED RESUME OF ORGANISMS OBSERVED 

 Phylum MOLLUSCA 



class GASTROPODA 



Order opisthobranchiata 



The Bermuda region is the only area in the northwestern 

 Atlantic where Pteropod Ooze forms the characteristic 

 bottom deposit. Therefore, although pteropods are not es- 

 pecially numerous in our deep-sea nets, it is not surprising 

 that they were constantly seen from the bathysphere at all 

 levels. Indeed, they were so prevalent that it was only 

 when larger animals were absent that I reported them. 

 They did not, however, compare in numbers with the 

 copepods and sagitta. The shell shapes of the various genera 

 are so characteristic that with a little practice I had no 

 difficulty in identifying them from the bathysphere win- 

 dow. They showed no trace of luminescence, though in the 

 beam their shells looked silver by reflected light. In swim- 

 ming they flapped their fleshy wings rapidly up and down. 

 Like all the other small creatures they were constantly in 

 motion, and were unaffected by the beam. 



Order prosobranchiata 



Firola was observed at three separate depths; 400 feet 

 (two fifteen-inch individuals); 1700 feet (several), and 

 2650 feet (one, twelve inches long) . This latter appeared 

 dully luminous all over, but showed no distinct illumined 

 areas. Several times we have taken specimens, measuring 



