10 Dr. P. P. Carpenter on new Forms of Mollusca 



4:7. Odosiomia tenuisculpta. 



O. testa ovoidea, subelevata, albida, tenui, diaphana ; anfr. nucl. 

 subvertiealiter imtnersis, angustis ; norm, iii., parum tumidis, su- 

 turis impi-essis, , sulculis spiralibus latioribus baud impressis, dis- 

 tantibus, in spira iii., circa basim rotuudatam circ. vi. siibobso- 

 letis ; apertura ovata ; plica acuta, declivi, parva, parieti contiijua; 

 labro acuto ; labio indistincto ; columella aiitice parum effusa. 

 Long. •!, long. spir. '04, lat. 06, div. 60°. 



Hab. Neeah Bay; one specimen {Swan). 



48. Scalaria Indianorum. 



S. testa gracili, turrita, alba ; anfr. circ. x., rotundatis, parum sepa- 

 ratis, Isevibus ; basi simplici, baud umbilicata ; costis viii.-xv. 

 (plerumque xii.), acutioribus, subreflexis, interdum latis, plerumque 

 lineis irregularibus margini spirse recto parallelis ascendeiitibus, 

 rarius juxta suturam subnodosis ; apertura ovata. Long. 1*05, 

 long. spir. -8, lat. -36, div. 28°. 



Hab. Neeah Bay {Swan). 



Strung as ornaments by the Indian children. Intermediate 

 between S. communis and S. Turtonis, and scarcely differs from 

 " S. Georgettina, Kien.," Mus. Cum. no. 34, Brazil. 



48 Z>. Scalaria {^.Indianorum, var.) tincta. 



8. I.Indianorum costis acutis, baud reflexis ; anfractibus postice fusco- 

 purpureo tinctis. 



Hab. Cerros Island {Ayres) ; S. Pedro {Cooper). 



The Lower-Californian shell may prove distinct. It is like 

 S. regularis, Cpr., but without the spiral sculpture. 



Subgenus Opalia, H. & A. Ad. (diagn. auct.). 



Scalarice varicibus obtusis, irregularibus, parum definitis : sculp- 

 tura basim versus interrupta. 



Ex. in Mus. Cum. : — 0. crassicostata, O. crassilabrum, 0. dia- 

 dema, 0. funiculata, 0. crenata, 0. granulosa, O. australis, O. bi- 

 carinaia, 0. attenuata, Pse., O. M'Andrea, Pbs., sp. ined. (Wcit 

 Indies). Other West-coast species are O. crenatoides and var, 

 insculpta, 0. spongiosa, and 0. i-etiporosa. 



The species of this very natural group were arranged by Messrs. 

 Adams partly under Opalia and partly under Cirsotrema. 



49. Opalia borealis, Gld. 



0. testa 0. australi simillima, valde elongata; anfr. xii., planatis, suturis 

 parum impressis ; testa jun. costis validissimis viii. latis, rotundatis, 

 peripheriam attingentibus, inter Jum interruptis; testa adulia stepiua 



244 



