614 iiEPOKT — 1863. 



Bo. 



attends their identification. Dr. Cooper found very large yalves (reseniHjn'' 

 Schizotharus) in abundance, but much deformed by the enti-ance of sand, and 

 apparently killed by the fresh waters of the gi'eat flood. The large shells 

 belong to two very distinct species, which are probably those of Conrad ; 

 among the small shells is perhaps a third, which may be Dr. Gould's sup- 



136. Eaeta undulata. This remarkable reverse of the Atlantic R. canaliculata is 



also confirmed by rare valves from the S. Diegan district. It is not con- 

 generic with Harvella elegans, to which it bears but a slight external resem- 

 blance. 



137. lapes tenerrima. Large dead valves of this very distinct species were found 



with the Standellm, and confirm Col. Jewett's young shells described as from 

 Panama. 



138. Fecten paucicostatm. Sta. Barbara Is. [Described from Col. Jewett's valves.] 



139. JBulla Quoyii. S. Diego. Maz. Cat. no. 226. 



140. Truncatella Californica. S. Diego. 



141. Acmrsa rosacea. Monterey to S. Diego. This shell is named ^lYcofas, Midd., 



in Mus. Cuming, but does not agTee with the diagnosis. It can hardly be 

 distinguished from Herm specimens of A. virginea. It was first brought by 

 Col. Jewett, but referred to Panama. 



142. Amphithalamus inelums. S. Diego. [Several specimens of this minute but 



remarkable new genus confirm a solitary shell in Col. Jewett's mixed 

 collections.] 



143. Mmrella simplex. Very variable in sculpture, as befits the species which 



iorms the northern limit of a group common between the tropics. Col. 

 Jewett's shell was in poor condition, and supposed to be the young of a 

 Gulf species. 



144. Volvarina varia. S. Diego, Cat. Is. [Sta. Barbara, Jewett; also C. S. Lucas.] 



145. Nassa Cooperi, Fbs. S. Diego, Cat. Is. [This Kellettian shell has a doubia 



right to its name, now that Dr. Cooper has ascertained its habitat.] 



The information on station, &c., which Dr. Cooper has sent with regaxd to 

 previously known species, wiU be found incorporated in the general table of 

 the fauna. The following notes, extracted from his letters, are too valuable 

 to be omitted : — 



Haliotis Cahforniensis. " This form is so rare that I think it only a vai. of 

 CracherodiV 



Haliotis. Several specimens from the Farallones present characters inter- 

 mediate between corrugata, rufescens, and Kamtscliaihana. It is not yet 

 ascertained whether they are hybrids or a distinct species. 



" Livona picoides I have not found, though I have seen fresh ones from Pt. 

 Conception." 



" ?Serputorbis squamigerus. Common south of Pt. Conception ; has no 

 operculum." [The young begins like V. anellum, Morch.] 



Macron Uvidus. Point Loma, S. Pedro, common ; extends northwards to the 

 Farallones. [=P!anaa;is nigritella,'N ewconih, MS.; non auct.] 



" Olivella sejnistriata, Gray, fide Newc., is a species found N. of Monterey only." 

 [As Dr. Gray's species is from Panama, that of Newcomb is probably 

 0. haitica.'] 



" Kassa interstriata, Com-., foss. (P=iV! paupera, Gld.) ; resembles N. fossntn, 

 Gld. (=S. elegans, Rye.*), but distinct. Common south from Sta. Barbara.' 

 [Probably =iV. perpinguis, Hds. N. paupera is quite distinct, = JV. striata, 

 ' 0. B. Ad., teste Cuming.] 



" Msswella molaoea I have seen fi'om Catalina Is." [Esoh.'s shell is generally 

 considered S. American. ? May Dr. Cooper's be a form of volcano.^ 



Acmcece. With regard to limpets and other variable shells. Dr. 0. -VNTitea :— 

 " From my examination of large numbers of specimens, I am more and 

 more compelled to believe that hybrids are very frequent between allied 



* Nassa elegam was first published, by J. Sowerby, in tlie Min. Conch. 182-i. 



100 



