50 



ed by the remarkable constriction near the suture. Specimens 

 were brought from the mouth of the Columbia, by Lewis and 

 Clarke, and have been designated by the above name. 



Natica caurina. Testa parva, solida, levigata, globoso-ellip- 

 soidea, albida, epidermide tenui stramineo induta, vix perforata : 

 spira obtusa, erosa, anfr. 4^-, ultimo sub-tabulato, antice sub- 

 contracto ; apertura parva, semilunaris ; columella recta, postice 

 callo copioso albo induta. Axis ^, diam. § poll. Hab. Straits of 

 De Fuca. 



Nearly the same as N. impervia, Phil, from Cape Horn, which 

 has a very depressed spire, and its umbilic closed by a semicir- 

 cular callus. Its form and color is like N. immaculata, Tott., 

 though it is much larger. It is more solid and less globular than 

 N. Grcenlandica. 



Natica soluta. Testa parva, globosa, sordide alba, striis 

 tenuissimis cincta : spira anfr. 5 ventricosis, superne sub-tabula- 

 tis ; sutura profundissima : apertura semilunaris, angulo postico 

 callo firmato ; labio acuto, tenui, ad basim incrassato, subeffuso : 

 columella recta, callosa, post umbilicum parvum profundum dila- 

 tata. Diam. 4 poll. 



A small, nearly globular shell, allied to N. borealis, Gray, and 

 N. globosa, King, but distinguished by its deep-channeled suture. 



Xatica algida. Testa parva, tenuis, globosa, glabra, albido- 

 livescens : spira anfr. 4 ventricosis juxta suturam linearem tabu- 

 latis, ultimo magno ampullaceo: apertura semilunaris; colu- 

 mella arcuata : basis umbilico modico spirali funiculato, ad aditum 

 angulato, perforata. Long, f ; lat. -| poll. Hab. Rio Negro. 



Dilfers from N. soluta principally in its sutural region, and in 

 its umbilical region, in which latter respect it differs from several 

 allied species such as N. globosa, N. borealis, &c. 



Natica dilecta. Testa parva, globulosa, solida, sub epider- 

 mide sordida eburnea, lineolis rubiginosis araneosis scutulata et 

 prope suturam lituris castaneis maculata : spira rotundata, anfr. 5 

 ventricosis: apertura semilunaris ; labro crasso ; columella valde 

 callifera, callo antice et ad funiculum castaneo, et canali trans- 

 verso fere diviso ; umbilico amplo, funiculo fere impleto. 

 Long, f ; lat. | poll. Hab. ? 



Has a general resemblance in size and form to N. maroccana. 



