DENTALIUM. 193 



This Dentalium, if placed in a vessel of sea-water 

 without sand, is evidently uneasy : it contrives to jerk 

 about slowly and clumsily, by attaching the central point 

 of its foot like the sucker of a leech ; and then, spread- 

 ing out the side lobes to their full extent triangle-wise, 

 it doubles up the foot, and twists itself round with a 

 sort of flapping movement. If placed in a bed of sand, 

 deep enough to cover the shell at a moderately inclined 

 angle, the foot becomes conical and elongated, and soon 

 eff'ects a passage for the whole body, leaving only the 

 top uncovered, to keep the gills supplied with water 

 or air. The ^ Proceedings of the Zoological Society "* for 

 1864 contain some interesting particulars of the use 

 and mode of capture in Vancouver's Isle and British 

 Columbia of D. pretiosum (Nuttall), which appears to be 

 identical with our species. Mr. Lord says that these 

 shells were employed as money by the Indians of North- 

 west America before the introduction, by the Hudson's 

 Bay Company, of blankets, which to a great extent 

 superseded the tooth-shells as a medium of purchase. 

 " A slave, a canoe, or a squaw, is worth in these days as 

 many blankets ; but it used to be so many strings of 

 Denialia.^' The value of a Dentalium depends upon its 

 length. Twenty-five long shells, strung together end to 

 end, make a fathom, and are called a " Hi-qua.'' At one 

 time such a string would have been worth about £50 ster- 

 ling. The shells inhabit the soft sand, in the snug bays 

 and harbours that abound along the west coast of Van- 

 couver's Island, at a depth of from 3 to 5 f. The habit 

 of the Dentalium is to bury itself in the sand, one end of 

 the sheU being invariably downwards, and the other end 

 close to the surface. " This position the wily savage 

 turns to good account, and has adopted a most ingenious 

 mode of capturing the much-prized shell. He arms 



VOL. III. K 



