684 heport— 18G3. 



before considered as essentially tropical. Along with these are not only some 

 species of types hitherto regarded as almost exclusively Asiatic, as Verticordia, 

 Solariella, and Fulvia modesta, but also some which belong to the sub-boreal 

 district, as Lucina horealis, Venericardia borealis, and Crenella decussata. The 

 latter belongs to the British, and not to the N. England form. 



129. Of the blendingof the temperate and tropical faunas on the peninsula of 

 L. California we are still in ignorance. All we know is, that at Margarita Lay 

 the shells are still tropical, and that at Cerros Island they are strangely inter- 

 mixed. There is peculiar evidence of connexion between the faunas of the penin- 

 sula and of S. America, not only in the land-shells (v. antea, p. 630), but in 

 some of the marine forms. Beside identical species with wide range, as many Ca- 

 lyptrseids, the following are coordinate between the North and South Pacific: — 



Upper and Lower California. 

 Netastoma Darwinii. 

 Solecurtus Califomianus. 

 Semele rupium. 

 Callista var. puella. 

 Chama pellucida. 

 Liocardiura substriatum. 

 Axinasa (Barbarensis.) 

 Verticordia novemcostata. 

 Pecten sequisulcatus. 

 Siphonaria thersites. 

 Tonicia lineata. 

 Acmaea patina. 

 AcmiBa persona. 

 SciuTia mitra. 

 CMorostonia funebrale. 

 Mitra maura. 

 lianella Caiiforniea. 

 Priene Oregonensis. 

 Trophon multicostatus. 



South America. 

 N. Darwinii. 

 S. Dombeyi. 

 (Ditto, Galapagos.) 

 0. pannosa. 

 C. pellucida. 

 L. Elenense. 

 A. intermedia. 

 V. ornata. 

 P. ventricosus. 

 S. lateralis, &o. 

 T. lineolata. 

 A. scutum, D'Orb. 

 A. " Oregona," ^. a 

 S. scurra. 

 0. mcestiun. 

 M. maura. 

 R. ventricosa. 

 P. cancellata. 

 T. Magellanicus. 



Time and space do not avail for pointing out further relations with exotic 

 faunas ; which indeed will be performed with greater correctness after Dr. 

 Cooper shaU have published his complete lists. 



130. For the sake of avoiding the inconvenience of trinomial nomenclature, 

 the subgeneric and varietal names have often been cited in this Eeport instead 

 of the generic and specific, in order that the exact form of the shell quoted 

 might be more quicldy determined. The diagnoses of all the new species 

 here tabulated are written for the press, and will shortly appear in the dif- 

 ferent scientific journals. Additional specimens will probably prove several 

 forms to be conspecific which are here treated as distinct. In the present 

 state oi the science, absolute certainty is not to be attained. The object of 

 the writer* has been principally to bring together the works of his prede- 

 cessors, and so to arrange and describe the new materials that those who 

 continue his labours may be able to draw their own conclusions from existing 

 data. In order to facilitate reference, a brief index is here given of tho 

 subject-matter of the former and of the present Eeports. 



* The best thanka of the writer are due to Hugh Cuming, Esq., for the free use of his 

 coEeotion ; to Messrs. H. & A. Adams, Hanley, Beeve, and Sowerby, for aid in identifying 

 specimens ; to the officers and naturalists conneoted with the Smithsonian Institution • 

 to Dr. A. A. Gould, for very valuable corrections j and generally to authors and friends' 

 who have kmdly rendered him all the assistance in their power. He earnestly invites 

 criticisms on the subject-matter of the two Reports ; in order that they may be embodied 

 and errors corrected, in the Manuals of the West-Coast MoUusoa which he has undertaken 

 to prepare for the Smithsonian Institution. 



Warrington, Aug. 2,2,nct, 1864. 



