174 



extus lirulis radiantibus subimpressis margines versus conspicuis 

 disco obsoletis ; lineis increment! conspicuis remotis fluctuosis ; intus 

 cicatricibus elongatis ; linea, palliali interrupts, punctata ; valvae altera? 



dente cardinali subulato, lateralibus subobsoletis ; valva? altera? ? 



Lono-. 3.75; alt. 3; lat. 2 millim. Inhabits St. Simon's Bay. W. S. 

 Only one valve was found. The bands of growth are alternately 

 opaque and diaphanous, and the pallial line is broken into dots as in 

 Lucina proper. 



Cryptodon polygonius. T. parvula, tenuis, fragilis, lucida, 

 alba, globoso-quadrata, striis incrementi leniter insculpta ; umbonibus 

 medianis eminentibus, tumidis ; extremitate antica, acuta, ; extrem. 

 postica latiori, oblique truncatii, angulo postero-ventrali acuto ; mar- 

 gine ventrali et margine antica continuatim arcuata ; portione postico 

 angulis binis radiato. Long. 4 ; alt. 3.5 ; lat. 3 millim. Inhabits 

 Simon's Bay. Cape Good Hope. W. S. 



It is larger, more equal in its diameters, thinner and more angular 

 in front than C. flexuosus. 



Scintilla thoracica. T. parva, tenuis, lucida, nitida, elongata, 

 tumida, subovalis, minutissime radiatim striata et fasciis concentricis 

 etiam punctis lacteis ornata ; umbonibus antemedianis, minutis ; ex- 

 tremitate antica rotundata ; extrem. postica altiori, oblique subtrun- 

 cata ; limbo tenuissimo ; cicatricibus bene impressis. Long. 13; alt. 

 8 ; lat. 4 millim. Inhabits Ousima. W. S. 



Lucina (Myrtea) seminula. T. minuta, crassa, albida, globoso- 

 trianeularis, sulcis et laminis elevatis undulatis subcrenulatis ad ex- 

 tremitatibus fere spinosis insculpta ; umbonibus vix post-medianis ; 

 lunula cordata, profunda, et postice fovea, ligamentali lanceolate 

 instructis ; junctione dorsali antico angulato ; ab umbone ad junctionem 

 antero-ventralem striata; extremitate postica biangulata, sulco ab 

 umbone aream minus insculptam secernente : cardo validus ; margine 

 interiori crassa penitus crenulata. Diam. 3 niillhn. Inhabits Hong 

 Kon"- harbor. Common in 5-10 fathoms, shell sand. W. S. 



Ilemarkable for its great solidity and the depths of its scidpture. 



Lucina (Codakia) parvula. T. oblique ovato-cordiformis, tenuis, 

 flavescens, tumida, concentrice laminato-lirata et radiatim striata, 

 striis utrinque excurvatis et interdum divaricantibus, intersectionibus 

 indentatis ; umbonibus elevatis, post-medianis ; lunula excavata ; mar- 

 gine interna exigue crenulata ; dente laterali antico obsolete. Long. 

 7 • alt. 6 ; lat. 4 millim. Inhabits Port Lloyd, Bonin Island ; Loo 

 Choo ; Hakodadi, in sand, 6 to 20 fathoms. W. S., and Captain 

 Rodgers. 



The characters are much the same in C. obliqua Rv., a much larger 

 shell. Specimens from Hakodadi are less deeply sculptured, and 



