The valves of many varieties of these shells are well adapted to the use of man. Not large enough for food vessels, they make most satisfactory spoons and cups, and are frequently found to retain portions of the pigments left from the last toilet of the primeval warrior and destined for use in the spirit land. It is probable, however, that they were much more frequently employed as knives and scrapers, and as such have played their part in the barbaric feast of the primitive village, or have assisted in the bloody work of scalp-taking and torture. They are pretty generally distributed over the country, and their occurrence in the mounds will probably have but little importance in the study of artificial distribution. Very little trouble has been taken by explorers and writers to identify the numerous species collected. _Haliotis._--The _Haliotis_ affords one of the best examples of the varied uses to which the natural shell has been applied by savage peoples. Recent explorations conducted by the government exploring parties in California have brought to the notice of archæologists and the world the existence of a new field of research--the burial-places of the ancient tribes of the Pacific coast. Many of the interments of this region are probably post-Columbian. Several species of this beautiful shell were used and are taken from the graves in great numbers, the pearly lusters being almost perfectly preserved. Many were used as paint-cups, and still retain dark pigments, probably ochers; one of these, a fine example of the _Haliotis californianus_, is shown in Fig. 4, Plate XXI. Some had contained food, and in a few cases still retained the much-esteemed _chia_ seed, while in others were found asphaltum, which was employed by these peoples in a variety of arts, the rows of eyes in the _Haliotis_ usually being stopped with it, and in one case, as shown in a specimen in the National Museum, it has been used to deepen a cup by building up a rim around the edge of a shallow shell. Many others are quite empty, and doubtless served as bowls, dishes, and spoons, or were ready at hand for the manufacture of implements and ornaments. Buried with the dead, they were designed to serve the purposes for which they were used in life. This shell probably formed as important a factor in the commerce of these tribes as did the large conchs of the Atlantic coast in that of the mound-builders and their neighbors. In recent times they are known to have a high value attached to them, and Professor Putnam states[2] that a few years ago a horse could be had in exchange for a single shell of the _Haliotis rufescens_. This species is a great favorite toward the south, and the _Haliotis Kamschatkana_, which furnishes a dark greenish nacre, is much used farther north.