Henry Gray (18251861). Anatomy of the Human Body. 1918.
The crown is large and conical, very convex on its labial surface, a little hollowed and uneven on its lingual surface, and tapering to a blunted point or cusp, which projects beyond the level of the other teeth. The root is single, but longer and thicker than that of the incisors, conical in form, compressed laterally, and marked by a slight groove on each side.
FIG. 1003 The permanent teeth, viewed from the right. The external layer of bone has been partly removed and the maxillary sinus has been opened. (Spalteholz.) (See enlarged image)
The upper canine teeth (popularly called eye teeth) are larger and longer than the lower, and usually present a distinct basal ridge.
The lower canine teeth (popularly called stomach teeth) are placed nearer the middle line than the upper, so that their summits correspond to the intervals between the upper canines and the lateral incisors.