184 



MEDITERRANEAN PROVINCE. 



are Nueula emarginata and striata, Cardium pa- 

 pillosum, Cardita acideata, and Dentalium novemcos- 

 tatum. 



Echinoderms are frequent here ; not so Zoo- 

 phytes. 



Terebratulce increase. This is the proper zone of 

 T. detruncata and Crania ring ens ; T. seminula 

 makes its appearance. 



Bivalves fifty-six ; at their maximum, twenty-five. 

 Univalves seventy-six ; at their maximum, thirty. 



The Sixth Region reaches from fifty-five to 

 seventy-nine fathoms. The sea-bed is here covered 

 with Nullipores; and Fuci are extremely few. Though 

 such is the case, there is still found here a con- 

 siderable number of Phytophagous Mollusks, and 

 which feed on the vegetable Nullipores. 



The Testacea which are most generally diffused 

 are Venus ovata, Cerithium lima, and Pleurotoma 

 MaravigncB ; those most prolific are Turbo san- 

 guineus, E mar g inula elongata, JSfucida striata, Venus 

 ovata, Pecten similis, and the various species of 

 Brachiopods. 



Below fifty fathoms, the range of each set of 

 Mollusks extends wider as we descend. 



Oidaris hystrix is the characteristic Echino- 

 derm. 



The Bivalves are forty-six, with seventeen at 

 their maximum. The Univalves about forty, with 

 twelve at their maximum. 



