ON MOLLUSCA OF THE WEST COAST OF NO11TII AMERICA. COT 



No. 



65. " Succinea rusticana, Gld." Sumass Prairie, Eraser B., Lord. [Scarcely to be 

 distinguished from the European S. putris.~\ 



06. "Planorbis corpulentus, Say." Lake Osoyoos; Syniakwateen; Marsh, Koo- 



tanie East, Brit. Col, Lord. 



57. Planorbis ? subcrenatus, var. Snmass Prairie, Brit. Col., Lord. 



58. " Limncea stagnalis" typical, fine, and abundant. Lake Osoyoos, Fraser B., 



Lord. 

 68. Limncea stagnalis^ long narrow spire, mouth swollen, closely fenestrated. 



Marshy stream, Syniakwateen, Lord. 

 CS. "Limncea ?desidiosa, Say." Lake Osoyoos; three sp., Lord. [Exactly le- 



sembles a var. of the widely distributed L. cataracta, which was found in 



profusion in the Madison Lakes, Wise.] 



60. "Limncea ?desidiosa, Say." Syniakwateen, Brit. Col., Lord. One sp. [Very 



turrited, whirls swollen; epidermis finely striated. The same species occurs 

 as " L. megasoma, Say. Lake Osoyoos."] 



61. (f Physa heterostropha, Say." Sumass Prairie, Fraser B. A variety from Lake 



Osoyoos, Lord. 



62. Physa [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 : 



C3. Terebratula wiguiciduSj n. s. Vane. Is., Forbes. One adult specimen, Mus. 

 Cum. [Extremely interesting as being the only sculptured species known 

 recent. The young shells from California were naturally affiliated to 

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

 the loop similarly incomplete.] 



C4. Rhynconella psittacsa. Vane. Is., Forbes. One specimen, Mus. Cum. 



C5. Darina declivis, n. s. Vane. Is., Forbes. One specimen. [The only other 

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



C6. dementia svbdiaphana. Vane. Is., Forbes. One broken sp. 



07. 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 Ccdlista, without lunule. 



The mantle-bend is remarkably small for the genus. 

 68. Melania, n. s., teste Cuming. Vane. Is., Forbes. [Two specimens, with very 



fine spiral stria?, sent to Philadelphia for identification.] 

 C9. 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 

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

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

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

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

 When such reliable data are thus fonnd 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 

 MageUanica and Trophon Magellanicus, duly marked " Vancouver's Island/' 

 though no 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 Vancourer 

 Island is beyond question. How it got "then* I do not pretend to say j it was very pos- 

 sibly brought by some ship," 



93 



