These taste papillæ generally have the form of a truncated cone and often are surrounded by a shallow circular pit, outside of which, in turn, is sometimes a small low wall. They are distributed over the entire dorsum of the tongue, usually at considerable distance from each other in comparison to the size of the tongue, and are not so numerous as the taste papillæ of the Mammalia. Rathke found their absolute number greatest in _A. lucius_. Rathke mentions other larger and harder projections on the tongue of certain Crocodilia which, though not perforated by a mucous duct, he thinks are of questionable relation to the sense papillæ. They usually have more the form of a flattened than of a truncated cone, and are very numerous in some species. _The Roof of the Mouth._ In the paper mentioned above the author notes that the papillæ on the roof of the mouth are evenly distributed and are more distinct than those of the dorsum of the tongue. One of these papillæ as seen under fairly high magnification is shown in Figure 40. [Illustration: FIG. 40. The covering of the roof of the mouth of the hibernating animal, under fairly high magnification; _a_, areolar tissue; _e_, epithelium; _h_, horny layer; _f_, fibers of horny layer.] The areolar tissue, _a_, forming the base of the section is of about the same character as seen in the section of the tongue. Less than one tenth of the thickness of the entire areolar base is shown in this section. The epithelium, _e_, where not thrown into papillæ, has also about the same character as that of the anterior region of the tongue--the same number of cell layers and the same distinct horny layer. At intervals the thickness of the cellular part of the epithelium is greatly increased, and at the same time the horny layer is also thickened, to form distinct papillæ like the one shown in the figure. These, as has been said, are comparatively small and have the shape of a blunt cone. The center of the cone is, of course, made up of the cellular epithelium, while the outside is covered with the thickened horny layer from which fibers, _f_, are often seen projecting. Near the apex of the cone the nuclei are larger and more widely scattered than those at the base. No glands were seen in the roof of the mouth of the hibernating animal, but since the entire roof was not sectioned it is probable that they may exist in some regions; in fact, as noted below, sections through the posterior region of the roof of the mouth of the feeding animal do show numerous glands.