. Anatomischer Anzeiger. Anatomy, Comparative; Anatomy, Comparative. 745 The elevated primitive triangle (Trigon) with a primitive cutting, piercing or sectorial function. The depressed heel (Talon), with a primitive crushing or grinding function. In the earliest stages the upper and lower molars were simple triangles of cusps, as in the modern Cape Mole, Chrysochloris. The lower molar had the apex (protoconid) turned outwards and the base (para- and metaconids) turned inwards, while the upper molar had these relations reversed. As shown in the accompanying diagram, Figure 2, the opposition of
. Anatomischer Anzeiger. Anatomy, Comparative; Anatomy, Comparative. 745 The elevated primitive triangle (Trigon) with a primitive cutting, piercing or sectorial function. The depressed heel (Talon), with a primitive crushing or grinding function. In the earliest stages the upper and lower molars were simple triangles of cusps, as in the modern Cape Mole, Chrysochloris. The lower molar had the apex (protoconid) turned outwards and the base (para- and metaconids) turned inwards, while the upper molar had these relations reversed. As shown in the accompanying diagram, Figure 2, the opposition of these triangles makes a perfect cutting mechanism, and as Cope has shown this is effective at every stage of development. If the protocene were at the outer angle of the upper molars, it is impossible to conceive of an effective series of inter- mediate stages. The first step towards the crushing function is the development of the hypoconid upon the incipient talonid which is later reinforced by two more cusps, the entoconid and hypoconulid. Thus the en- tire heel or talonid is complete upon the lower molars before it commences to develop upon the upper molars, as shown in Anaptomorphus (Fig. 1, 7 and Fig. 3, 9) as well as in the ontogeny. Upon the upper molars the talon is only developed in bunodont types, such as the Primates and Ungulates, to still further increase the crushing area of the crowns; it always arises as seen in the ta-lorvid. trigon. nr tr. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Anatomische Gesellschaft. Jena : G. Fischer
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