ON MOLLUSCA OF THE WEST COAST OF NORTH AMERICA. 571 



lives there. The shell here figured is beaked like Nuttatti, no. 49 ; lu- 

 nule very faint ; concentric ridges very faint, but sharp ; radiating ribs 

 verv coarse. Inside deeply stained ; margin not ere lated on the sharp 

 anterior edge, though faintly on the lunule ; hinge-teeth stumpy.] 



CO. Venus musearia, Rve. Hob. ? [Has the aspect of a West Coast species, 

 between cardioides and fine var. of staminea ; sinus large ; teeth strong, 

 not biiid ; lunule with radiating ribs.] 



C8. Venus undtitella, Sby. Gulf Calif. [Not a satisfactory species, the type 

 havin<r the aspect of a poor specimen altered for cabinet. The " sculpture 

 much changing in its development towards the margin " is an accident 

 often seen in the cancellated species. Similar specimens of V. nenlecta, 

 no. 54, collected at Cape St. Lucas b^y Mr. Xantus, agree with urulatetta 

 in all respects, except that this is violet within, neylccta being white. 

 Ligament-area (as in neglecta) smooth in one valve only.] 



77. Venus Adamsii, Rve. Japan. [Closely related to Tapes laciniata, San Diego, 

 in size, aspect, hinge, &c. Differs in mantle-bend being not so long or 

 pointed, and the radiating sculpture much finer := V. rigida, Gld., MS., in 

 Stimpson's list; non Gld. in l Otia.'] 



80. Venus omatissima, Brod. Panama, sandy mud, 10 fms., Cuming. Still unique. 

 [Like V. ffnidia, jun., but radiating ribs coarser and more distant ; con- 

 centric frills not palmated ; lunule pale, laminated.] 



87. Venus callosa [Sby., non] Conr. Sandwich 4 Is. and Calif. [Vide note to no. 

 59. This is the V. Nicttattii of the Brit. Assoc. Report. Those who regard 

 it as distinct from. fluctifraga, of which gibbosula, no. 47, is the extreme 

 form, may retain the name callosa of Sby., but not of Conr. Conrad's 

 species = C. nobilis, Rve. ; differing from the true Oa&iste, as Mercenaria 

 does from Venus, in having the ligament-plate rugose.] = V.fluctifraga, 

 Sby., teste Rve. in errata. 



105. Venus biUneata, Rve. Gulf Calif. Partakes of the characters of compta 

 and subimbricata: all three may indeed be different states of one and the 

 same species. [The shell figured at 1056 has all the peculiar features of 

 compta, which are clearly marked within; only the concentric waves are 

 closer than usual. The shell figured at 105a appears to be the true wt- 

 datella, only in fine condition, the type being rubbed. It has exactly the 

 same internal characters, including colour; only the colour-lines outside 

 are arranged in rays instead of V s - Mr- Reeve, however, retains his differ- 

 ent opinion.] 



116. Venus Ct/pria, Sby., P. Z. S. 1852. Is. Plata, West Columbia. [From sani3 

 district, teste Schott in Mus. Smiths.] Has all the appearance of being 

 an attenuately produced form of the West Indian V. papliia [which is 

 also from Cape Verd Is., teste Macgillivray in Brit. Mus.]. 



11. Dione* maculata, List. West Indies ; Brazil; Pacific Ocean. Widely distri- 

 buted in both hemispheres. [No authority for the Old World ; the Pacific 

 shells are Callista chioncsa, var.] 



15. Dione nobilis, Rve., 1849. Cal. [=C. callosa, Conr., 1837. The original 

 name, from type, had been communicated to Mr. R., but is not quoted. 



20. Dione semilamellosa J [,(j(^\\A.., C.lupanaria, Less. Centr. Am. [ = lupinaria, 



Maz. Cat, no. 95. Vide Deless. Rec. Coq. pi. 19. f. 2 : " China Seas," no 

 authority.] 



21. Dione breviyrinata, Ttve., = brevispina, Sby. [Gulf of ] California. [Scarcely 



differs from C. rosea, jun.] 



22. Diane multispinosa, Sby. Peru. Concentric ridges thinly laminated ; spinrs 



slender and numerous. [An extreme form of the Pacific C. Dione (tes;e 



Hani.) ; distinct from semilamellosaJ] 

 23. Dione Veneris, D'Arg. Conch, pi. 21. f. l,= V. Dione, Ln. West Ind. 



and 



* The figured types of this genus had been accidentally mislaid ; and might alter the 

 judgments given in the text. 



t " For obvious reasons, I think it best to abandon the foul name given to this lovely 

 species by Lesson," Rve. (Vide Maz. Cat. p. 70, note.) ? We old not the same reasons 

 lead to the alteration of meretrix, impudica, &c. 



57 



