FIG. 26 in Cranial Morphology And Phylogenetic Relationships Of Trigonostylops Wortmani, An Eocene South American Native Ungulate

FIG. 26. Trigonostylops wortmani AMNH VP-28700. A, B, basicranium in rostroventral aspect, with interpretative diagram based on updated version of Simpson's (1933a) figure 5, drawn in similar orientation; C, left auditory region (stereopair) in oblique rostroventral aspect, to reveal matrix-filled rostral (piriform) part of basicapsular fenestra; and D, left auditory region (stereopair) in oblique caudoventral aspect, to reveal close proximity of tympanic cavity and aditus of extratympanic sinus. In A, contour lines on basicranium rostral to ectotympanic (not in original illustration) approximate extent of matrix-filled basicapsular fenestra (see C). Labeling conforms to identifications and nomenclature used in this paper. Key: 1, caudal carotid incisure in ectotympanic; 2, Simpson's "foramen lacerum medium & Eustachian canal," actually medial limit of matrix-