256                                      APPENDIX.
0. CLASS MOLLUSCA.
The shells described in the following pages constitute but a small portion of the collection obtained during the expedition. Those collected on St. Peter's river were packed in a box, and intrusted to the men who returned in canoes to Fort St. Anthony; this box has not yet been received, and is supposed to be lost. On the subsequent part of the route I put all the univalves collected, iu a canteen which I constantly carried, but which was finally lost at Mackinaw. Another parcel of shells sent from Chicago has not since been heard of. To this statement of our losses I may add a still more important one, consisting of a box which contained skins of quadrupeds, birds, reptiles, and fishes.
HELIX.
1. H. harpa. Shell conic, reddish-brown; whorls four, convex, with numerous elevated, subequidistant, equal, lameliform, acute lines across, the interstitial spaces flat and wrinkled; aperture suborbicular, truncated by the penultimate whorl, and very little oblique; labrum simple; umbilicus small, nearly concealed by the base of the labrum.
Length rather more than one-tenth of an inch.
Inhabits the North-west Territory.
The elevated lines on this shell give it a very handsome appearance, and readily distinguish it from any of our native species that I have seen. The European analogue is the aculeata of Muller, but our shell is destitute of recurved points on the lameliform lines. PI. 15, fig. 1.