ON MOLLUSCA. OF THE WEST COAST OF NORTH AMERICA. 679 



20. Sphcerium occidental^ Pr., Proc. A. N. S. Phil. 1860, p. 295, = C. ovalis, Pr., 



Bost. Proc. 1852, p. 276 (nom. preoc.),=< Sph. ovale, Stn.,' Add. Gen. vol. ii. 

 p. 450. H(ib. New York to Georgia j Vermont to Wisconsin ; Hell-gate 

 River, W. T. 



21. Sphcerium nobile, Gld. (Cyclas n.\ Bost. Proc. 1855, p. 229 [Otia, p. 218]. San 



Pedro, Webb. 



22. Sphcenum patella, Gld. (Cyclas p.), Bost. Proc. 1850, p. 292 [Otia, p. 86 j E. E. 



Moll. f. 527, type not returned to S. I.] Oregon. 



23. Sphcerium Spokani, Baird [P. Z. S. 1863, p. 69, f. 12, 13 : antea, p. 605]. B. Col. 



24. Sphcerium tumidum, Baird [P. Z. S. 1863, p. 69, f. 11 : antea, p. 605]. B. Col. 



25. Sphcerium meridionale, Pr., JProc. Ac. N. S. Phil. 1861, p. 414. Panama ; Mus. 



Prime. 



26. Sphcerium lenticula, Gld. (Lucina * I.), Bost. Proc. 1850, p. 256. California. 



27. Sphcerium subtransversum, Pr., P. Z. S. I860, p. 322. Mexico. 



28. Pisidium abditum, Hald. [?ubi] = Cyclas minor, C. B. Ad. Bost. Proc. 1841, p. 48, 



= P. obscurum, Pr., Bost. Proc. '1851, p. 161,+ P. Kurtzii, Pr., p. 162, + P. 

 zonatum, Pr., p. 162,+P. regulars, Pr., Bost. II. vi. 363, pi. 12. f. 11-13, 1852, 

 + P. notatum, Pr., Bost. II. vi. 365, pi. 12. f. 20-22, 1852, +P. amplum + P 

 resartum, Ingalls, MS.,+P. rubrum+P. plenum, Lewis, MS., +P. retusum, 

 Pr., P.Z.S. 1859, p. 322. 



29. Pisidium occidental, Newc. [Proc. Cal. Ac. Nat. Sc. 1861, p. 94]. San Fran- 



cisco, Rowell. 



120. Of the tertiary fossils throwing light on existing species no addi- 

 tional information has yet been published. We cannot but hope that the 

 researches of Mr. Gabb, on the fossils collected by the Californian Geological 

 Survey, will develope relations of great interest between the existing and 

 former conditions of the continent. The Astorian fossils described by Mr. 

 Conrad from the U. S. Exploring Expedition (vol. x., Geology, Philadelphia, 

 1849), and tabulated in the first Report, p. 367, belong to the Smithsonian 

 Institution, but were not discovered there in 1860. All of them, however (in- 

 cluding the indeterminate species), are figured in the atlas of plates. They 

 resemble the fossils of the Pacific Railroad Expeditions in being very imper- 

 fect, for which reason the following criticisms may prove erroneous. The 

 general aspect of the collection betokens the Miocene period. 



My a abrupta, Conr., may be the young of Glycimeris generosa, Gld, 



Thracia trapezoides, Conr., may be curta, Conr. 



Solemya ventricosa, Conr., has the aspect of a large Lazaria. 



Tcllina arctata, Conr., closely resembles Macima, var. expansa. 



Tellina emacerata, Conr., is perhaps Bodegenria. lids. 



iMcina acutilineata, Conr., appears to be borealis, Linn. 



Cardita subtenta, Conr.,== Venericardia borealis, Conr. 



Nucula divaricata, ConT.,=Acila castrensis, Hds. 



Pectunculus patulus, Conr., may be sevtentrionalis, Midd. 



Pectunculus nitens, Conr., resembles Psephis tantilla, Gld. 



Pecten propatulus, Conr. A very fine specimen, enclosed in a large nodule 

 from Oregon, was presented to the Brit. Mus. by Mr. C. Pace. If not identical 

 with Amusium caurinum, Gld., it is most closely allied, especially to the 

 Japanese form. 



* Mr. Prime assigns no reason for changing Dr. Gould's Lucina into a Cyclas, nor any 

 authority for " California." He was, perhaps, misled by the artist's engraved references to 

 the figures 528, a, b, where he has drawn a rule, referring to the Cyclades above, instead of 

 writing Lucina. It is assigned to "?Coast of Patagonia" in 'Otia,' p. 63, and to "?R. 

 Janeiro" in ' E. E. Moll.,' p. 414. In each place the shell is compared to an Astarte or 

 Cyprina, with lateral teeth. The type was not returned to the Smithsonian Institution ; 

 but the diagnosis states that it is " chalky, thickened within the deep and jagged pallial 

 line, sculpture faint but decussated, and margin finely crenulated," characters more con- 

 sistent with Lucina, s. g. Myrtcea, than with Cyclas. If the type cannot be recovered, per- 

 haps the species may be dropped, as it is not the Lucina (Myrt&a) lenticula, Eve. 



165 



