Along with the types not stemmed are such specimens as are shown at the bottom at the right of Fig. 77; possibly that one was a drill, but I have included the three under the classification we have been following—without stem, base straight, base convex and pointed. Yet these typical Pacific Coast leaf-shaped artifacts are different from the forms found East. In specimens with stems especially in the Susquehanna and Delaware Valleys, and the greater part of the Mississippi Valley are occasionally found chipped implements with straight sides and the points sharply contracting. Some of these will be shown under the proper divisions. This angular effect of the object is intentional and merits a class by itself as much as do the objects which are classified according to stem form alone. In Fig. 68 are beautiful specimens from Maine, Mr. Marks’s collection. In these six we have the simple form of knife, well chipped, the pointed knives, the oval and pointed knife, and the two beautiful spear-heads, which, of course, come under a later classification. The spear-head to the left is of that cloudy quartzite approaching agate, which is also found in Arkansas and Wisconsin, and a material of which some of the finest specimens in the United States have been manufactured by our aborigines. [Illustration: FIG. 77. (S. 1–1.) Serrated obsidian points (or knives). Typical of California artifacts. F. M. Gilham’s collection, Highland Springs, California. ] [Illustration: FIG. 78. Obsidian problematical chipped objects. Sizes and locality stated on the specimens. Dr. H. M. Whelpley’s collection, St. Louis, Missouri. ] Figs. 72 and 75 represent the sub-class C, more or less circular. A splendid example of the knife with square ends is shown at the left in Fig. 73. Also a knife with one edge straight and the other convex is shown in the same figure, and the specimen is labeled E 268. Fig. 72 marks the transition stage from the oval knife to the slightly stemmed or shouldered spear-head. All these are Wisconsin specimens from Mr. S. D. Mitchell’s collection and the collection of Beloit College. Oval knives, or oval chipped objects, may range from minute specimens a half an inch in length to magnificent problematical forms in obsidian shown in Fig. 78. A few such as these have been found in ancient graves or burial-places in California and Oregon. The workmanship on them is not quite as fine as on the “ceremonial swords” from Tennessee shown in Plates 161 and 162, but obsidian was more easily chipped than Tennessee chert. An inspection of the Tennessee objects referred to and these immense obsidian blades, and a comparison between them and the objects found elsewhere in the world, proves that the American aborigine did not have a superior on this globe in art forms of neolithic types. Fig. 75 illustrates the circular discs, and the almost circular knives, and by way of comparison is added the oval knife.