ON MOLLUSCA OF THE WEST COAST OF NORTH AMERICA. 607 
No. 
55. “ Succinea rusticana, Gld.” Sumass Prairie, Fraser R., Lord. [Scarcely to be 
distinguished from the European 8S. putris. | 
56. “ Planorbis corpulentus, Say.” Lake Osoyoos; Syniakwateen ; Marsh, Koo- 
tanie East, Brit. Col., Lord. 
57. Planorbis ? subcrenatus, var. Sumass Prairie, Brit. Col., Lord. 
58. “ Iimnea stagnalis,” typical, fine, and abundant. Lake Osoyoos, Fraser R., 
Lord 
58. Iimnea stagnalis, long narrow spire, mouth swollen, closely fenestrated. 
Marshy stream, Syniakwateen, Lord. 
59. “ Limnea ? desidiosa, Say.” Lake Osoyoos; three sp., Lord. [Exactly re- 
sembles a var. of the widely distributed Z. cataracta, which was found in 
rofusion in the Madison Lakes, Wise. | 
60. “ Jitkes Pdesidiosa, Say.” Syniakwateen, Brit. Col., Lord. One sp. [Very 
turrited, whirls swollen; epidermis finely striated. The same species occurs 
as “I, megasoma, Say. Lake Osoyoos.” | 
61. “ Physa heterostropha, Say.” Sumass Prairie, Fraser R. A variety from Lake 
Osoyoos, Lord. 
62. Physa {probably young of Lordi, but with orange band inside labrum.] Koo- 
tanie R. East, Brit. Col., Zord. One sp. 
Besides the shells preserved in the National Collection, the following 
species were also brought by the Expedition :— 
63. Terebratula unguculus, 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 Hanley ; but the adult has 
the loop similarly incomplete. | 
64, Rhynconella psittacea. Vance. 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. Clementia subdiaphana. Vance. 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 Callista, 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 striz, sent to Philadelphia for idenieeeatau] 
69. Mesalia lacteola. Vance. 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 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 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 Vancouver 
_ Island is beyond question. How it got there I do not pretend to say; it was very pos- 
sibly brought by some ship.” 
