ON MOLLUSCA OF THE WEST COAST OF NORTH AMERICA. 5C9 



7. Orhktda osfreuides, Lain.,= O. Norvegica, Sby. (non Lam. )+ O. striata, Sby.+ • 

 Crania radiosa, Gld. + O. \^Discina] Evansii, Dav. F N. W. Africa. " The 

 locality, ' Budeiras, Cal.,' given by Mr. D. with O. Evamii, on Mr. Cuniiujr's 

 authority, nuist, I think, l)e a mistake." [The genus has not been found 

 on the Califomian coast by any American collector.] 



8 Vetim* grata, Sby.,+ 'xWor, Sby. Gulf of Mexico, Mus. Cum. [=Tapea 

 grata. Say, Panama. The locality-labels have probably been misplactd. 

 These sprcimens are undoubtedly from the W est Coast, nor has any 

 authority appeared for the species in the Atlantic. The Gulf of Mexican 

 " analogue ' is T. granulata. \ he forms are intermediate between Chione 

 and Tit pes. ~\ 



9. Venus multirostnta. Sby. Bay of Panama, in coarse sand at low water, Cuming. 

 "Probably= T''.Z*'s/('/-/.var.,with ribs more tumidly thickenod androundtd." 

 [The West Coast shells are distinguished by the very slight ci-enulation 

 of the ribs at the sides.] 

 19. Venus asperrima, Sby. Guacomayo, Centr. Am., sandy mud, 1.3 fms., Cuming. 

 "A form oi pi'ciorina ; shAl of lighter substance, broader and more de- 

 pressed ; scidpture more elevately and definitely latticed." [This is the 

 shell named by Mr. Cuming V. cardioidcs, Lan\, and should take that 

 name, as prior to Sby."s, if really distinct from pectorina. Also from 

 I'anama. Mus. Smiths.] 

 22. Venus du<cors, Sby.. jun. St. Elena and Guacomayo, Centr. Am., sandy mud, 

 6-9 fms., Cuming. "Concentric decussating ridge.s cease abruptly at the 

 posterior third." [Character very variable, even in the type-.speciniens ; 

 = T. grata, Say, var.] 



25. Venus pectorina, Lam., p. 344,+ V. cardioides. Lam. Centr. Am., Mus. Cum, 



[Probably Atlantic : much heavier and stumpy ; sculpture coarser ; tetth 

 more like casina, whereas cardioides, no. 19, has a long anterior tooth 

 like sugillata f.] 



26. Venus cingu/ata, ].am.,=pulicaria, Brod. W. Columbia, Cuming. [=V. 



Pinaciifensis, Sloat, MS. in Mus. Smiths. Guaymas. The peculiar 

 smoothing-otl" of the central sculpture in the adidt may be varietal. It 

 is iuiprobnble that Lam. was acquainted with the species.] 



33. Venus crenuhda, Ch^'va.,■=crennta, (Jmel. W. L = V. eximia,'V\\\[.,-^ V. ere- 

 nifera, i^hy.,+ J'. Portesiana, D'Orb. [\ot to be confounded with the 

 P". creniferu, Maz. Cat. : has a small Cyprinoid lateral tooth, but no 

 radiating ribs near lutiule, nor long anterior tootht.] 



85. Venus CulifurHien4s, Brod.,= V. h-ucodon, Sby. Guavnia.s, Gulf Cal., sandy 

 mud, low water, [teste] Cuming. Mus. Cum. [= V. crassa, Sloat, MS. in 

 Mus. Smiths. Not V. Califontitma, Conr.,= V. simillitna. Sby. This 

 species, with V. neglecta, compta, &c., having the mantle-bend nearly 

 ODSolete, approach Annmalorardia subimhricata, and with that species 

 form a natural group, ditiering from the typical Vemts as Lioconcha dots 

 from CuUista : = V. suvcincta, \'al.] 



41. Venus Kennerleyi, Cpr., MS. % in Mus. Cum. Hob. — ? [Puget Sound, 

 Kennerh'y.~\ 



43. Venus sugillata, Rve. California, Mu.s. Cum. Characterized by the shining 

 purple umbos, finely latticed sculpture, dark-stained hmu'e and liga- 

 mentary aria. [ = " V. crenifera, Sby., teste Rve.," Maz. Cat. no. I't.'i, 

 in all essential characteis. jjiliers in the long anterior tooth being still 



• Through the kindness of Mr. Eeeve, with a view to the complrtion of this Eeport, 

 I was enabled to compare the figui-ed specimens in this genus with the text, and witli 

 the shells of the vSuiithsonian coUectioji, before they were distributed. The bracketed notes 

 in the text are based on this cxaniination. They are given with miusual detail, because 

 of the unique opportunity of throwing some light on a confessedly difficult family. 



+ The characters of the teeth and pallial line frequently aflford satisfactory daagnostio 

 marks between critical species, which are often oTerlooked by monographers. 



X The descriptions of Dr. Kennerley's shells had long bct>n written, and would hare 

 boon ))ublished but for the Anierinan war. The localities of all the West Coast shells sent 

 from the SmitLs. Col. to All'. Cuming nere dul^ mai'kcd in the accompanying catalogues, 



6&-' 



