893 iiEPORT — 18G3. 



a^c. The typos of these spoHes in the Smithsonian Museum a, ^'•n, t.^o im- 

 perfect to determine specitically with any confidence ; and by no nleaIl^ ii. « 

 suitable condition to allow of important conclusions being drawn from them. 

 98. The third article in the Appendix to the same volume of Kejiorts 

 contains a " Catalogue of the Recent Shells, with Descriptions of the New 

 Pjiecics," by Dr. A. A. Gould. The specimens were (apparently) in the hands 

 of Dr. Gould for examination when he prepared the MS. for the first Report; 

 and some of them were included in the "Mexican War Collections," B. A. 

 Report, pp. 227, 228. " The freshwater shells were collected in the Colorado 

 desert and other localities ; the land and marine shells between San Francisco 

 and San Diego." The following is the hst of specie? as determined by Dr. 

 (.'ould, pp. ;330-33(). The specimens belong to the Smithsonian Institution, 

 where a large portion of thcTu were fortunately fh'scovered and verified. 

 They were collected by W. P. Blake, Esq., and Dr. T. H. Webb. 



Plate. Fig. No. 



1. 0.<frfa, sp. ind. Parasitic on twigs ; thin, radiately lineated with 



brown. [ = 0. cmwhanfii'la, CTpr.'\ Another species, elongated, 

 solid, allied to Viri/inica [rar. rufoidei]. San Diego. 



2. Pecten motiotinien'g, C'onr. San Diego. 



8. Pecten veidricosm, Shy. ,+tumi(his, Sby. [Dead valves, of the 

 form (eqiiisulcatiis.! San Diego. 



4. Mf/iilmiedulU [ = M. trosulu^, Gldi.y ante(l\. San Francisco. 



5. Modiola rapajr, Conr. San Die<ro. 



G. Venus Xuttullii, Conr. \_=V. guccincta, Val.] San Pedro. 



7. Venus fliictifriif/a, Sby. San Diego. 



8. Ta/)es ffrata, Say,= t. discors, Sby., "zsstraminea, Conr."* San 



Pedro. 



XL 19,20. Q. Tape i ffracilis, Cxld., U.S. Prel. Hep. 1855. [Quite distinct from 

 every other 7'«;>«s known from the coast. It is supposed by 

 Dr. Cooper to be the young of Saxidomm aratu<, wliich in 

 shape and pattern exactly accord with the figure nnd diagnosis. 

 But the " Tapis" is figured without sculpture. The shell was 

 not found at the Smiths. Inst.] San Pedro, Blake. 

 10. Cyclas, sp. ind. Colorado Desert. 



XT 21,22. 11. Cardimn cncentahnn, Gld., n.s. I'rel. Rep. 1855. [P. Z. S. 18.-)G, 



S201,= C'. substriatum, Conr.] San Diego. [San Pedr-.-, 

 lake, in text.] 



12. Lucina orbella, Gld. [ = " Mi/sia (^Spkarella) ttimida" Conr.] ShE 



Pedro. 



13. Lucina Nidtalln, Conr. San Pedro. 



14. Mewdesma frubrotincfa, Sby.t San Pedro. 



15. Tellina ricina, C. B. Ad. [Dead specimens of = Heterodotiax 



(" Psnmmobia,'^ var.) Pacifica, Conr.] San Diego. 



16. Tellina secta, Conr. San Pedro. 



17. S!)fi(sniti \_C'ryi)tomya'\Californica, Conr. San Diego. 



18. Petricola carclitoides,ConT.,=ci/lindracea,Desh. Monterey; San 



Pedro. 



19. Solcairtus Califomiensis, Conr. San Diego. 



20. Gnnthodon lA'contii, Conr., = G. tnffotMm,Vetit. Colorado Desert. 



[Leconiei is probably the large Texan species: trt</omts=meH' 

 dicus is a very distinct shell from Mazatlan.] 



* Neither Dr. Gould, nor Conrad himself, in his later geological writings, appears to 

 have called to mind the true T. staminea, to which the Smithsonian shells belong. It is 

 the northern representative of T. grata, but quite distinct : v. synonymy under Ven%t 

 Petitii=:riffida, pars. 



f- No " Mesodesma " was found among the shells returned to the Smithsonian Institu- 

 tion, nor has any been heard-ot from the coast. Dr. Gould's shell may have been Semel4 

 pulchra, which was in the collection. 



78 



