478 Dr. P. F. Carpenter on new Forms of MoUusks. 



31. "i Hydrohia compacta. 

 1H. testa Isevi, curta, compacta, latiore ; marginibus spirse vix ex- 

 curvatis ; anfr. nucl. normalibus, apice mamillato ; norm. iv>, tu- 

 tnidis, suturis distinctis ; spira curtiore ; basi rotundata j apertura 

 subovata ; peritremate continue ; labio definito. Long. '04, long, 

 spir. -02, lat. -03 poll., div. 70°. 



This unique shell may be a Barleeia. 



32. Hyala rotundata, 



H. testa (quoad genus) magna, tenui, alba, diaphana ; anfr. nucl. 

 normalibus, apice mamillato ; norm, iv., globosis, rapide augenti- 

 bus, suturis valde impressis ; basi rotundata ; apertura subrotua- 

 data, ad suturam subangulata ; peritremate continuo ; labio a 

 pariete separate, rimulam umbilicalem formante ; columella valde 

 arcuata. Long. '18, long. spir. -09, lat. -1 poll., div. 40°. 



A unique shell, resembling a marine Bithinia. 



33. ?Diala electrina. 



W. testa subdiaphana, rufo-cornea, nitida ; marginibus spirae parum 

 excurvatis ; vertice nucleoso, helicoideo ; anfr. iii., tumidis, suturis 

 hand impressis, apice magno mamillato ; anfr. norm, iii., subplanatis, 

 suturis distinctis ; sculptura baud expressa ; tota superficie cos- 

 tulis obscuris, latis, spiralibus, quarum vi.-viii. in spira monstran- 

 tur, et iii.-v. circa basim rotundatam, interdum obsoletis, cincta ; 

 costulis radiantibus circ. xviii., subobsoletis ; apertura regulariter 

 ovata, ad suturam angulata, peritremate continuo ; basi baud um- 

 bilicata; columella regulariter arcuata. Long. '09, long. spir. '07, 

 lat. -03 poll., div. 30°. 



34. Acirsa Menesthoides. 



A. testa nitida, turrita, majore, solidiore, pallide fusca ; anfr. nucl. 

 Isevibus ; norm, vi., subplanatis, suturis distinctis; lineis crebris 

 spiralibus insculpta, quarum circ. viii. in spira monstrantur ; testa 

 axiolescente lirulis radiantibus obsoletis decussata ; apertura sub- 

 ovali; columella solida, imperforata. Long. "42, long. spir. "3, 

 lat. -16 poll., div. 25°. 



35. Cythnia asteriaphila. 



C. testa C. tumenti simillima, sed umbilico minore, hand carinato ; 

 tenuissima, diaphana ; anfr. iv., tumidis ; vert. nucl. normali, baud 

 stylineo, apice mamillato : operculo tenuissimo, elementis concen- 

 tricis, nucleo submediano sinistrorsum sito. Long. '03, long, 

 spir. -015, lat. -025 poll., div. 60°. 



A solitary specimen was found by Dr. Stirapson, imbedded in 

 a star-fish, like Stylina ; from which genus the vertex and oper- 

 culum distinguish it. 



36. Bittium nitens. 



B. testa regulari, rufo-fusca, hie et illic pallida, maxime nitente ; 



