198 



valves are closed, is flat, with angular crenated edges. It was 

 dredged in sandy mud, at a depth of nine fathoms. — G. B. S. 



Nucula polita. Nuc. testd oblongd, antice rostratd, albd, epi- 

 dermide virescente, politd ; margme dorsali anticd Icevi ; striis 

 nonnullis obliquis anticis : long. J 'At, alt. 0'6, lot. 0*45 poll. 



Hab. ad Panamam. 



A single specimen of this very beautiful species was dredged up 

 in sand from a depth of seven fathoms. — G. B. S. 



Nucula Pisum. Nuc. testd parva, oblique ovali, latere antico 

 brevissimo, margine dorsali inclinatd : long. 0*25, lat. 0' 15, alt. 

 0-2 poll. 



Hab. ad Valparaiso. 



Dredged in coarse sand and gravel, at various depths from seven 

 to forty fathoms. — G. B. S. 



Nucula costellata. Nuc. testd oblongdy tenui, antice ros- 

 tratd, acuminatd, costis duabus dorsalibus approximatis, crenu- 

 latis ; costellis acutis concentricis, totam superficiem tegentibus : 

 long. 0*8, alt. 03, lat. 0'2 poll. 



Hab. ad Panamam. 



Two specimens were taken in sandy mud at a depth of ten fa- 

 thoms. A thin epidermis covers the shell. — G. B. S. 



Nucula gibbosa. Nuc. testd oblongd, gibbosd, antice acuminato- 

 rostratd, longitudinaliter sulcata ; dorso antico depresso, margi- 

 nibus centralibus elevatis : long. 12, lat. 0*55, alt. 0*6 poll. 

 Hab. ad littora Peruvian 



Found in soft mud, at a depth of five fathoms, at Tumbez in Peru. 

 A variety, with a less elevated ridge in the centre of the anterior 

 dorsal margin, and of much smaller size, was found in mud, at 

 twelve fathoms, in the Gulf of Nocoiyo. — G. B. S. 



Nucula Elenensis. Nuc. testd ovatd, gibbosd, longitudinaliter 

 sulcata, antice rostrato- acuminata ; limbo dorsali antico arcuato, 

 marginibus crenulatis : lofig. 0*5, lat. 0*25, alt. 0*35 poll. 



Hab. ad Sanctam Elenam. 



Dredged in sandy mud at a depth of six fathoms. — G. B. S. 



Nucula eburnea. Nuc. testd ovata, gibbosd, longitudinaliter 

 sulcatd, nitidd, eburned, antice rostrato-acuminatd : long. 0*65, 

 lat. 0-3, alt. 0-35 poll. 

 Hab. ad oras Columbiae Occidentals. 



Found in sandy mud, at a depth of from seven to nine fathoms, 

 in the Bay of Caraccas. — G. B. S. 



Nucula cuneata. Nuc. testd ovato-cwieiformi, gibbosd, epider- 

 mide Qirescente, nitidd., latere postico rotundato, antico acuminato ; 

 superficie concentrice sulcatd : long. 0*4, lat. 0'2, alt. 0*25 poll. 



Hab. ad Valparaiso. 



Dredged in coarse sand and gravel, at various depths, from four- 

 teen to forty-five fathoms. — G. B. S. 



Nucula exig&a. Nuc. testd parvd, oblique ovatd, albicante, pel- 



