197 



ventrali antico rotundnto, postico leviter flexuoso ; umhonibus ni- 

 gricanti-purpurasccntibus : long. 3*3, alt. 2*3, lat. 1-35 poll. 

 Hab. in Peruvia et America Centrali. 



Dredged among coarse gravel, in twelve fathoms water, in the 

 Gulf of Nocoiyo. A smaller variety, which is also rather higher, 

 was found at Tumbez, at a depth of five fathoms, in thin mud. — 

 G. B. S. 



Genus Solenella, G. Sowerby. 



Testa ovalis, cequivalvis, subcetjuilateralis, compressa, nitens, epi- 

 dermide olivaceo-viridi, tenui, indnta ; dentibus cardinalibus 

 nullis, lateralibus anticis in utrdque valvd, tribus ad quatuor^ 

 lateralibus posticis plurimis, seriem rectiusculam effbrmantibus, 

 omnibus parvis acutis ; impressionibus muscularibus duabus, la- 

 teralibus, subdistantibiis ; impressione pallii sinu magna .- liga- 

 mento externa, elongate. 

 An interesting new genus of marine bivalves, in which the general 

 form and characters of M. Blainville's Soletiocurtus are combined 

 with the series of minute sharp teeth characteristic of Nuciila. It 

 appears to belong to the family of the Solenacece, and it may at 

 once be separated from the Madracece, to which Nucula belongs, 

 by the circumstance of the whole of the ligament being external. 



Solenella Norrisii. Sol. testd allido-ccerulescente ; epidermide 

 olivaceo'viridi, zonis concentricis saturatioribus : long, \'6, alt, I, 

 lat, 04 poll. 



Hab. ad Valparaiso. 



Discovered by Mr. Cuming, in soft mud, at from fourteen to 

 forty-five fathoms depth. 



This is the only species of the genus I have seen ; but Mr. Cuming 

 informs me that he obtained a single valve of another and very dif- 

 ferent species. By the specific name I wish to honour and keep in 

 remembrance Thomas Norris, Esq., of Redvales, near Bury, 

 Lancashire. — G. B. S. 



Genus Nucula. 



Nucula elongata. Nuc. testd elongatd,lanceolatd, tenui, albd, 

 epidermide Jiiscd prope marginem ventj-alem indutd ; subcequi- 

 fatcrali, latere antico breviore ; margine dorsuli rectiusculd, pos- 

 tlce subreflexd ; serie dentium posticd divaricatd : long. 2'^, lat, 

 0-25, all. 0-7. 



Hab. in Columbia Occidentali. 



Dredged in sandy mud, at a depth of twelve fathoms, at Xipi- 

 xapi. 



Nucula ciienifera. Nuc. testd elongatd, lanccolatd, Icevigatd, 

 ienuissime longitudinaliter striatd ; marginibus dorsalibus cari- 

 natis, carinis concinne crenulatis: long, 1'4, alt. 0*4, lat, 0*2 poll, 



Hab. ad Xipixapi. 



This species approaches nearly in shape to Nuc. lanceolata ; it is, 

 however, broader and higher, and its dorsal margin, when the two 



