218 PROCEEDINGS OF THE CALIFORNIA 



v. rotundatis, fere sequalibus, plus niinusve solutis, suturis subimpressis ; tota* 

 superficie tenue spiraliter striata ; striis in spirS majoribus, circ. viii. distanti- 

 bus, minoribus creberrimis iDtercalantibus ; circa basim rotundatam circ. x. 

 majoribus, contiguis. minoribus paucis ; apertura circulari, peritremati con- 

 tinuo, solido, ad suturam parum callosam appresso ; umbilico nullo. 



Long. 023, loDg. spir. 0-16, lat. 0-09, div. 12°. 



Hab. Monterey, 20 fm. 45, dead. Cooper. 



Genus Amphithalamus,* Cpr. 



Testa Rissoidea; nucleo magno ; apertura labio producto, labro subpostice 

 juncto, subito in adulta contracta. 



Type. Amphithalamus inclusus, Cpr. Br. Assoc. Rep. 1863, p. 656 ; Ann. 

 Nat. Hist, Jan. 1865. 



Hab. Santa Barbara, Jetvett ; S. Diego, in shell-washings. Cooper. 



? Amphithalamus lacunatus, Cpr. n. s. 



? A. t. adolescente "A. incluso " simili ; nucleo similiter minutissime et con- 

 fertissime spiraliter et radiatim striulato ; sed raajore, latiore, anfr. subplanatis ; 

 basi late lacunata, haud carinata ; adulta ?. . 



Long. 0-06, long. spir. 0-03, lat. 0-03, div. 50°. 



Hab. San Pedro. Cooper. 



Two dead specimens in the shell-washings of Dr? Palmer's consignment to the 

 Smithsonian Institute might have been passed over as the young of Barleeia 

 subtenuis, but for the possession of exactly the same remarkable nucleus as A. 

 inclusus. It is presumed, therefore, that they are congeneric ; if so, the adult 

 has not been seen. 



Genus Diala, H. & A. Adams. 

 Diala acuta, Cpr. n. s. State Collection, No. 390. 



D. t. parva, turrito-conica, cerina, polita, nitente ; anfr. nucl. ii. naticoideis, 

 vertice mamillata, apice iudistincto ; norm, v., omnino planatis, suturis indis- 

 tinctis ; peripheric acute angulata, vix carinata ; basi omnino planata ; aper- 

 tura subouadrata ; peritremati continuo ; labro postice paullum contracto ; 

 labio appresso ; columella antice angulata, vix sinuata. 



Long. 0-15, long. spir. 0-09, lat. 0-07, div. 29°. 



Hab. Catalina Is. 8-10 fm. ; on beach to Monterey. Cooper. 



Diala marmorea, Cpr. n. s. 



D. t. solida, exacte conica, lasvia, nitente ; subdiaphane pallida, rufo maculata ; 

 anfr. nucl. rotundatis, planorbeis, sub-oblique sitis, apice celato ; norm. vi. 

 planatis, suturis indistinctis ; basi planata, sub-angulata ; apertura ovali, per- 

 itremati continuo, haud varicose 



Long. 0-17, long. spir. 0*11, lat. 0-08, div. 31°. 



Hab. Monterey, S. Pedro ; Cooper. Lower California, off Haliotis. Rowell. 



* From the Greek for chamber on both sides. 



