The specimens illustrated are made from the thicker portions of species of the _Haliotis_ or of the valves of the dark purplish _Mytilus californianus_. They are handsome objects, their surfaces being well rounded and polished. In the collection there are specimens which illustrate very well the process of manufacture. A series of these is given in Plate XXVIII. Fig. 1 shows a small fragment broken out roughly from the shell, probably by a stone or shell implement. Fig. 2 shows a similar specimen in which an irregular perforation has been made. In Fig. 3 we see a considerable advance toward completion; the hole has been enlarged by rubbing or filing with some small implement, and the outline approximates that of the finished hook. Figs. 4, 5, and 6 represent typical examples of the completed hooks. These range in size from one-half to three inches in length, the width being but slightly less. The skill acquired in the manufacture of such objects of use is of the greatest importance in the development of art. It is only through the mastery of material thus engendered that the arts of taste become possible. [Illustration: PL. XXVIII--SHELL FISHING APPLIANCES. 1, 2, 3. Manufacture of hooks. 4, 5, 6. Hooks from graves, California. 7. Pendant or sinker, California. 8, 9. Pendants, Atlantic slope. (1/1)] WEAPONS. It would hardly seem at first glance that shells or shell substance could be utilized for weapons to any advantage. A close examination, however, of some of the more massive varieties will convince us that they could be made available. The specific gravity of some varieties, such as the _Strombus_ and _Busycon_, is equal to that of moderately compact stone, and with their long, sharp beaks they would, with little modification, certainly make formidable weapons. Dr. Charles Rau seems to have been the first to call attention to the use of shells as club-heads by the tribes of Florida. In his valuable paper on the archæological collections of the National Museum he gives a very good description, which I copy in full: "It further appears that the Florida Indians applied shells of the _Busycon perversum_ as clubs or _casse-tetes_ by adapting them to be used with a handle, which was made to pass transversely through the shell. This was effected by a hole pierced in the outer wall of the last whorl in such a manner as to be somewhat to the left of the columella, while a notch in the outer lip, corresponding to the hole, confined the handle or stick between the outer edge of the lip and the inner edge of the columella. The anterior end of the canal, broken off until the more solid part was reached, was then brought to a cutting edge nearly in the plane of the aperture. A hole was also made in the posterior surface of the spire behind the carina in the last whorl, evidently for receiving a ligature by means of which the shell was more firmly lashed to the handle."[48]