156 



Messrs. Carpenter and Jeffreys on [Dec. 8, 



sented new genera. The following is an analysis of the Mollusca (perfect 

 and fragmentary) taken in this one haul : — 





Total 









Orders. 



number of 



Eecent. 



Fossil. 



unde- 





species. 







scribed. 



Brachiopoda 



1 



1 







Conchifera 



50 



32 



1 



17 



Solenoeonchia .... 



7 



3 





4 



Gastropoda 



113 



42 



23 



48 



Heteropoda 



1 



1 









14 



12 





2 





186 



91 



24 



71 



The Northern species above referred to are 34 in number, and include 

 Mytilus (Dacrydium) vitreus, Nucula pumila, Leda lucida, L. frigida, 

 Pecchiolia abyssicola, Necera jugosa or lamellosa, N. obesa, Tectura 

 fulva, Fissurisepta papillosa, Cyclostrema sp. n., Torellia vestita, Pleuro- 

 toma turricula, Admete viridula, Cylichna alba, Cylichna ovata, Jeffr. 

 MS. = Bulla conulus, S. Wood, not Deshayes (Coralline Crag), and 

 Scaphander librarius. Leda lucida, Necera jugosa, Tectura fulva, Fissuri- 

 septa papillosa, Torellia vestita, and the undescribed species of Cylichna, 

 as well as several other known species in this dredging, are also fossil in 

 Sicily. Nearly all these Shells, as well as a few small Echinoderms, Corals, 

 and other organisms, had evidently been transported by some current to 

 the spot where they were found ; and they must have formed a thick de- 

 posit, similar to those of which many Tertiary fossiliferous strata are com- 

 posed. It seemed probable also that the deposit was partly caused by tidal 

 action, because a fragment of Melampus myosotis (a littoral Pulmoni- 

 branch) was mixed with deep-water and oceanic Pectinibranchs and La- 

 mellibranchs. None of the shells were Miocene, or of an older period. 



14. This remarkable collection, of which not much more than one half is 

 known to Conchologists, notwithstanding their assiduous labours, teaches 

 us how much remains to be done before we can assume that the record of 

 Marine Zoology is complete. Let us compare the vast expanse of the sea- 

 bed in the North Atlantic with that small fringe of the coast on both sides 

 of it which has yet been partially explored, and consider with reference to 

 the dredging last mentioned what are the prospects of our ever becoming 

 acquainted with all the inhabitants of the deep throughout the globe ! We 

 believe, however, that a thorough examination of the newer Tertiaries 

 would materially assist us in the inquiry ; and such examination is feasible 

 and comparatively easy. Much good work has been done in this line ; 

 but although the researches of Brocchi, Bivona, Cantraine, Philippi, Cal- 

 cara, Costa, Aradas, Brugnone, Seguenza, and other able Palseontologists in 

 the South of Italy have extended over more than half a century, and are 

 still energetically prosecuted, many species of Molluscous shells are con- 



