Figure 1. Examples of the two Siwalik upper canine morphologies, lingual view. Left: GSP 11003, a typical Sivapithecus canine; right: GSP 17121, an atypical canine. Note the wrinkled enamel, concave lingual face, deep mesial groove, straight cemento-enamel junction (cej), and stout root of GSP 11003, and the smooth enamel, convex lingual face, minimal or no mesial groove, sigmoid cej, and tapering root of GSP 17121. Actual specimen lengths: GSP 11003 = 44.7 mm; GSP 17121 = 41.7 mm.