from the West Coast of North America. 5 



329 b. Bit Hum (? vai*.) esuriens. 



B. testa B. floso simili, sed multo minore, graciliore, interdum vald- 

 attenuata ; sculptura testse juii. ut in B. filoso, testae adultse sub 

 obsoleta ; interstitiis hand insculptis. Long. "3, long. spir. '21 

 lat. -11, div. 25°. 



Hob. Sta. Barbara {Jewett) ; Neeah Bay {Swan) ; Monterey 

 {Cooper). 



334. Bittium fastigiatum. 



B. testa parva, gracili, pallide rufo-cinerea, marginibus spirae vix 

 excurvatis ; anfr. nucl. iii., Isevibus, tumidis, apice acute; norm, ix., 

 planatis, suturis alte impressis ; anfr. primis iii. carinatis, postea 

 costis radiantibus circ. xiii., obtusis, satis extantibus, ad suturas 

 interruptis, interstitiis uadatis, liris spiralibus iv. in S]iira se uion- 

 strantibus, costas undatim superantibus, quarum antica in testa 

 jun. plerumque extat; anfr. ultimo parum contracto, basi elongata, 

 liris spiralibus vi. contiguis ornata ; apertura gibbosa ; labro 

 acuto, interdum varicoso, antice angulatim emarginato ; labio 

 tenui. Long, -25, long. spir. -ID, lat. -09, div. 20°. 



Hah. Sta. Barbara {Jewett). 



Genus Amphithalamus*. 



Testa Rissoidea, nucleo m.ngno ; apertura labio producto, labro 

 subpostice juncto, subito in aduita contracto. 



355. Amphithalamus inclusus. 



A. testa minuta, lata, solidiore, pallide rufo-fusca ; vertice mamillato; 

 anfr. nucl. uiio et dimidio, quoad magnitudinem pennagnis, mi- 

 nutissime et confertissime spiraliter et radiatim striolatis ; anfr. 

 norm, iii., Isevibus, subplanatis, suturis impressis ; basi subangulata; 

 costa peripherica rotundata, baud extante, interdum in spira se 

 monstrante ; costa altera circa regionem pseudo-umbilicarem ; labro 

 acuto, hand contracto : labio testa adolesceiite normali, dein a 

 pariete separata, sinum posticum suturam versus formante, t. aduita 

 valde separata, regionem quasi umbilicarem magnam formante; ad 

 labrum subito fere perpendiculariter, subpostice juncto : operculr 

 tenuissimo. Long. "04, long. spir. "02, lat. -03, div. 60°. 



Hah. Sta. Barbara {Jewett); S. Diego {Cooper). 



This very remarkable little shell bears the same relation to 

 Rissoa that Stoastoma does to Helicina. The peritreme resem- 

 bles a figure ^ inverted, as on the face of the type. In the dis- 

 proportionate size of the nuclear whorls it resembles Vitrinella. 



373. Drillia mcesta, 



D. testa acuminata, Isevi, dense olivaceo-fusca, epidermide Isevi ad- 

 heerente induta ; anfr. nucleosis ?... (decoUatis); norm, viii., parum 



* Th. a/x^i, BaKafios, having a chamber ou both sides. 



283 



I 



