ON MOLLUSCA OF THE WEST COAST OF NOIITII AMERICA. C07 



Ko. 



65. " Siwct))en rnsticana, Qld.'" Sumass Prairie, Fraser R., iw(/. [Scarcely to be 

 distino'uisbed from the European S. jyiitris.^ 



56. ^' Planorhis corpulentus, Say." Lake Osoyoos; Sjiiiakwateen j Marsh, Koo- 



tanie East, Brit. Col., Lord. 



57. Planorbis Y siihcrenaius, var. Snraass Prairie, Brit. Col., Lord. 



58. " Limncfa sta(/nalis/' typical, iiuC; and abundant. Lake Osoyoos, Eraser R., 



Lord. 

 53. Limncpa stagtmlis, long narrow spire, mouth swollen, closely fenestrated. 

 Marshy stream, Syniakwateen, Lord. 



59. ^'' Linuuea ?desidiosa, Say." Lake Osoyoos; three sp., Lord. [Exactly re- 



sembles a var. of the widely distributed L. cataructa, which was found m 

 profusion in the Madison Lakes, Wise] 



60. " Li?)in(pa ?desidiosa, Sslj.'' Syniakwateen, Brit. Col., Lord. One sp. [Very 



tm-rited, whirls swollen ; epidermis finely striated. The same species occuj'S 

 ns '^ L. meffasoma, Say. Lake Osoyoos."] 



61. " Physa heterostropha, Say." Sumass Prairie, Eraser R. A variety from Lake 



Osoyoos, Lord. 



62. PJii/sa [probably young of Lordi, but with orange band inside labrum.] Koo- 



tanie R. East, Brit. Col., Lord. One sp. 



Besides the shells preserved in the National Collection, the following 

 species were also brought by the Expedition : — 



63. Terehratula nngincidKS, n. s. Vauc. Is., Forbes. One adult specimen, Mus. 



Cum. [Extremely interesting as being the only sculptured speci^'S known 

 recent. The young shells from California were naturally r.ffiliated to 

 Terebratella captd-serpentis by Messrs. Reeve and Ilanley ; but the adult has 

 the loop similarly incomplete.] 



64. Phijnconella psittacea. Vane. Is., Forbes. One specimen, Mus. Cum. 



65. Darina declivis, n. s. Vane. Is., Forbes. One specimen. [The only other 



species of Darina is from the West Coast of S. America.] 



66. Clernentia s'ibdiapkatia. Vane. Is., Forbes. One broken sp. 



67. Saxidomus brevisiphonatus, n. s. This unique shell is marked " Vancouver 



Island " in Mr. Cuming's Collection, and is believed by him to have formed 

 a part of Dr. Forbes's series. The shape resembles CulUsta, without lunide. 

 The mantle-bend is remarkably small for the genus. 



68. Melania, n. s., teste Cunving. Vane. Is., Forbes. [Two specimens, with veiy 



fine spiral strife, sent to Philadelphia for identification.] 



69. Mesalia lacteola. Vane. Is., Forbes. One sp., Mus. Cum. 



70. Pteropoda, several species, of which two are new, teste Cuming ; but they may 



have been collected on the voyage. Forbes. 



The collections made on the British Survey are peculiarly valuable to the 

 Btudent in consequence of the great perfection of the specimens. They have 

 generally been obtained alive, and are often the finest known of their kijuls. 

 The occurrence, however, of a specimen of the tropical Orthalkus zebra, 

 marked " Vancouver's Island," in Mr. Lord's collection*, is a useful lesson. 

 AYlien such reliable data are thus found possessed of adventitious materials, 

 it will not be regarded as a slight on the collections of the most careful 

 naturalists when specimens are regarded as of doubtful geographical accuracy. 

 In Dr. Lyall's collections there also occur specimens of the well-known Patella 

 Magellanica and Trophon Magellanicus, duly marked " Vancouver's Island," 

 though 110 doubt collected in the passage round Cape Horn. The naturalists 

 of the American Expl. Expeditions generally travelled across the continent. 



104. The latest exploration undertaken for State purposes is also for our 

 present object by far the most important, both as relates to the number of 



• Mr. Lord writes, "The fact of my having found this shell, alive, on VancouTer 

 Island is beyond question. How it got there I do not pretend to say ; it was very po»« 

 eiblj brouglit by some ship," 



93 



