Such a very concise description of these objects is given by Prof. F. W. Putnam in a recent paper that I beg leave to quote it here, omitting his references to figures: "A columella was ground down to the required size and shape, and made into a pendant by boring a hole through the larger end. In order to make this pendant still more attractive, the spiral groove is filled with asphaltum, or a mixture of that material and a red pigment. Sometimes the spiral groove was so nearly, or even wholly, obliterated in the process of grinding the columella into shape as to make it necessary to enlarge or even recut the groove in order to make a place for the much-loved asphaltum." Another form, made from another shell, is described, the whorls of which are "loose and open, so that a natural tube exists throughout the length of the spire; at the same time the spiral groove in the central portion is very narrow; consequently it has to be artificially enlarged for the insertion of the asphaltum, which thus winds spirally about the shell. As the natural orifice at the large end of the shell seems to have been too large for properly adjusting and confining the ornament as desired, this difficulty was overcome by inserting a small shell of _Dentalium_, or by making a little plug of shell, which is carefully fitted and bored."[58] The national collection contains upward of fifty of these pins, which come from ancient graves at Santa Barbara and Dos Pueblos, Cal., and from the islands of Santa Cruz and San Miguel. These vary in length from one to five inches, the well-finished specimens seldom reaching one half an inch in diameter. At the upper end they round off somewhat abruptly to an obtuse point, but taper to a sharp point at the lower end, something like a cigar. Two fine examples are shown in Figs. 1 and 2, Plate XXXI. All show the spiral groove, and nearly all have portions of the asphaltum remaining. The columellæ from which they are made may be to some extent naturally perforated, but are certainly not sufficiently so to permit the ready passage of a cord. The points are seldom sharp, and are often broken off. A bit of _Dentalium_ inserted into the perforation and set with asphaltum helps to enforce the point and to guard against further breakage. The larger specimens are seldom perforated transversely at either end, while the smaller ones are almost always perforated at the larger end, which is slightly flattened. A good example is shown in Fig. 5, Plate XXXI. A peculiar bulb-pointed specimen is illustrated in Fig. 6, Plate XXXI. The bulb is made from the upper end of the columella. There are six of these pins in the collection. The consideration of these pins leads naturally to the presentation of other classes of objects manufactured from the columellæ of marine univalves among which beads are the most numerous and important.