ON MOLLTJSCA OF TIIC WEST COAST OF NORTH AMERICA. 507 



work had been carelessly printed.) It contains the following species, tho 

 localities quoted in the text trom other sources being here omitted :— « 



Pap 



309. Mwrex foliaius, Gmel.,!=i!f. monodon, Each. {Cerosioma). San Diego, ? fossil, 

 Cassidy. 

 „ Miirex festivus, Hds. Dead. San Diego, Cassidy, 



„ Triton Oreffonensis, Redfield (non Jay, nee Say) = T. cancellatiim, Midd., 

 Rve., non Lam. Straits of De Fuca, Suckley, Gibbs, J. 6. Cooper. 



370. Chiysodomus antiquus, var. Behringiana, Midd., one specimen. Straits of De 



Fuca, Suckley. [Comp. Chr. tahtlatws.l 

 f, Chrysodomus Middendorffii, Coop., n. s.,= Tritonium decemcostatum, Midd. 

 One specimen on the shore of Whidby's Island. Straits of De Fuca, J. O. 

 Cooiptr. [=jBj«c. liratum, Mart. This being a remarlcable instance of a 

 "representative species," it requires to be minutely criticized. Judge 

 Cooper compared his specimen with 130 eastern shells, and noted the differ- 

 ences with great fulness and accuracy. A series of Middendorff's Pacific 

 shells having been brought to England by Mr. Damon, and sold at high 

 prices, I made a searching comparison of one of them with the eastern 

 specimens furnished me by Judge Cooper and other most trusty naturalists. 

 According to the diagnosis of Middendorffii, it should be referred to C. de- 

 cemcostatus, Bay, and not to the De Fuca species, as it agrees in all respects 

 with the eastern peculiarities quoted, except that the riblets near the canal 

 are rather more numerous and defined. As it might be suspected that 

 Mr. Damon's shells were mixed, I have made a similar comparison with a 

 shell from the N. W. coast, sent to the Smiths. Inst, by Mr. Pease, and with 

 the same result. On examining the specimens in the Cumingian Collection, 

 in company with A. Adams, Esq., we were both convinced that the eastern 

 and western forms could not be separated. In the similar shells collected 

 by Mr. Adams in the Japan seas there are remarkable variations in the de- 

 tails of sculpture.] 



371. Chrysodomns Sitchensis, Midd. l=incisiis, Gld.,=diiits, Eve.]. Str. De Fuca, 



Sacldey, Gibbs. 



„ Nassa mendica, Gld. Puget Sound, Suckley. 



„ Nassa Gibbsii, Coop., n. s. " Resembles N. trivittata more than JV. mendica." 

 Port Townsend, Puget Sound. [In a large series, neither Dr. Stimpson nor 

 I were able to separate tl.is species from N. mendica. Similar variations 

 are common in British J\'ass<B. Picked individuals fi-om the Neeah Bay 

 series would probably be named trivittata, if mixed with eastern shells.] 



I, Purpura lactuca, Esch. , + M. fevr^gineu^, Esch., = P. septentrionalis, Rve. Puget 

 Sound, Suckley, Gibbs; Shtialwater Bay, Str. de Fuca, J. G. Cooper. 

 "Abounds on rocks and dyster-beds in Shoalwater Bay, the form and 

 amount of rugosity depending on station. The oyster-eaters ai'e smooth 

 even when young." — J.G. C. 



372. Purpura ostrina, QIA., = P. D'eycinetii, Miii., non Desh. +P. decemcostata 



ECoop., non] Midd. Rocks above low- water mark ; from mouth of Hood's 

 'anal to Str. Fuca ; Puget Sound, common, /. G. Cooper. 

 „ Purpura lapittus JCoo^., non] Linn. [=-P. soaricofa, Val.] Str. De Fuca, 

 'Paget Sound,t7r<?. Cooper. "Found with P. ostrina, and equally common. " 

 [Some varieties run into the New England form of P. lapillus, sufficiently 

 nearly to justify the identification ; but the bulk Of the specimens are easily 

 distinguished hy the excavated columella. They pass by insensible grada- 

 tions to P. ostrina, Gld., which is a rare and extreme variety. Many of the 

 shells called P. Freycinetii lay Midd. are certainly referable to this species. 

 Some forms pass towards the true P. Freycinetii, Desh., while others are 

 equally close to the very different P. emarginata, Desh.] 

 „ Purpura emarginata, Desh., = P. Conradi, Nutt. MS. "Upper California," 

 Trask ; San Diego, Trowbridge. [This appears to be exclusively a .southern 

 ioTcn.=saxicola, var.] 

 „ Monoceros mgonatum, Conr., =i(f. unicarinatum, Sby. San Pedro, Dr. Trask- 



373. Monoceros lupilloides, Com:,=^3L punctaium, Gray. San Pedro, Di: Trask. 



