158 Pelagian Mollusca collected on a [no. 2, new series. 



a mass of them appeared like liquid fire of a bluish yellow color. 

 Most of the Crustacea we have caught are luminous, especially 

 their eyes. After 9 p. m, we caught in the net three small Hyalceas 

 one of them, Fig. 15, already described, the other kind delineated 

 in Fig. 16, had a more expanded aperture and the posterior extre- 

 mity was unusually lengthened and curved so as to give the shell 

 somewhat the form of a cornucopia. Another interesting shell 

 of which we obtained several specimens this evening, much resem- 

 bled a minute sinistral Helix, transparent, glossy, discoidal, with the 

 spire slightly elevated ; it is well represented and magnified in Fig. 

 8. I could not well distinguish the animal. It was extremely minute 

 and none of those I placed in water showed any signs of vitality. 

 I believe the shell to be a Limacina or Spiratella. These names 

 are by some authors considered synonymous, though others take 

 them to represent two different genera. The shell has likewise 

 been confounded with Atlanta ; and consequently the various des- 

 criptions of this shell, are most conflicting and contradictory. On 

 this account I regret the more, my not having been able to record 

 the appearance of the animal. However the figures of this and 

 indeed of all the species illustrated in the accompanying plates 

 are executed with such fidelity as to render it a comparatively 

 easy task for a Naturalist in command of the requisite means, 

 either to pronounce a species new, or to identify it with such as 

 have been already described. The animal is probably a Pteropod. 

 We took a few more specimens of it, the following night, after 

 which we saw no more of them. 



Our course was now south easterly for a considerable time, during 

 which our experiments with the net were almost barren of results, 

 and it was not until we approached higher and warmer lati- 

 tudes, that we again fell in with Mollusca. However, hard- 

 ly a day passed that our net did not reveal varied and 

 novel forms of animal life, with which the ocean seems 

 to be teeming,— beautifully marked fish, singular Crustacea 

 and a variety of Acaleph^:, as Beroe, Viphyes and Cuhoides, the 

 two latter perfectly transparent and angular, like animated crystals. 

 Many of these animals would live for days when placed in a vessel 

 of sea water and the study of their habits in this manner, was 

 always interesting and well calculated to while away a vacant hour, 



