from the West Coast of North America. 5 



329 b. Bittium (? var.) esuriens. 



P. testa B. fiJoso siinili, sed multo minore, graciliore, interdiim vald 

 atteimata ; sciilptiira testse jim. ut in D.Jiluso, testae adultse sub 

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

 lat. -11, div. 25°. 



Hab. Sta. Barbara [Jeivctt) ; Neeah Bay {Swan) ; Monterey 

 {Cooper). 



334. Bittium fastigiatum. 



B. testa j)arva, gracili, pallide rntb-cinerea, marginibus spirae vix 

 excurvatis ; anf'r. nncl. iii., Isevibus, tnmiilis, apice acute; norm, ix., 

 planatis, suturi ^ alte inipressis ; ant'r. primis iii. carinatis, postea 

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

 interruptis, interstitiis uiidatis, liris sj)iralibus iv. iu s|)ira se nion- 

 strantibus, costas undatini superantibus, quarum antica iu testa 

 juu. plerumque extat; aut'r. ultimo i)arum coutracto, basi elongata, 

 liris spiralibus vi. contiguis ornata ; apertura gibbosa ; labro 

 acuto, interdum varicoso, autice angulatini emarginato ; labio 

 tenui. Long, 'lb, long. spir. 'VJ, lat. 'DO, div. 20°. 



Hab. Sta. Barbara [Jewett). 



Genus Amphithalamus*. 



Testa Rissoidea, nucleo niagiio ; apertura labio producto, labro 

 subpostice juucto, subito in adulta coutracto. 



355. Amphithalamus inclusus. 



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

 anf'r. unci, uiio et diuiidio, quoad magnitudinem ))erinagnis, nii- 

 nutissime et coutertissiiiie spiraliter et radiatim striolatis ; anf'r. 

 norm, iii., laEvibus,sul)plauatis, suturisimpressis ; basisubangulata; 

 costa peripberica rotuudata, hand extante, interdum in spira se 

 monstrante ; costa altera circa rcgionem pseudo-umbilicarem ; labro 

 acuto, baud coutracto : lal>io testa adolescente normali, dein a 

 pariete separata, siuum ])Osticum suturam versus formante, t. adulta 

 valde separata, regionem quasi umbilicarem maguam formante; ad 

 labrum subito fere perpendiculariter, subpostice juncto : opercul*^ 

 tenuissimo. Long. •04, long. s])ir. 02, lat. "03, div, GO^. 



Hab. Sta. Barb:ui {Jewett); S. Diego {Cooper). 



This very remarkable little shell bears the same relatiou to 

 Rissoa that Stoastoma does to Helicina. The peritrenie resem- 

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

 proportionate size of the uue'ear whorls it resembles Vitrinella. 



373. Drillia mo'sta, 



J), testa acuminata, Irevi, dense olivaceo-fusca, epidermide Inevi ad- 

 hcerente iuduta ; anf'r. nucleosis?...(decollatis); norm, viii., paiuui 



* Th. dix<f)\, ddXafios, having a chamber on both sidei. 



283 



