. Anatomischer Anzeiger. Anatomy, Comparative; Anatomy, Comparative. 743 cusp of the talon, hyd. In Miacis of the lower eocene (6) the figures of the internal and crown views of the three molars show how the primitive anterior portion (trigonid) of the crown was reduced to the level of the posterior portion (talonid) while retaining all of its cusps. In the next figure (7) we see the lower molars of the oldest monkey or lemur known, Anaptomorphus, which illustrate the. na mc' Fig. 1. Evolution of the Cusps of the Human Lower Molar. loss of the antero internal cusp or paraconid, pa*1, — this is
. Anatomischer Anzeiger. Anatomy, Comparative; Anatomy, Comparative. 743 cusp of the talon, hyd. In Miacis of the lower eocene (6) the figures of the internal and crown views of the three molars show how the primitive anterior portion (trigonid) of the crown was reduced to the level of the posterior portion (talonid) while retaining all of its cusps. In the next figure (7) we see the lower molars of the oldest monkey or lemur known, Anaptomorphus, which illustrate the. na mc' Fig. 1. Evolution of the Cusps of the Human Lower Molar. loss of the antero internal cusp or paraconid, pa*1, — this is present as a rudiment in m1 and m2 but has disappeared in m3. This accounts for the history of all the cusps in the human lower molar. Thus in the rich series of mesozoic x) and lower eocene Mammals we can observe the actual rise, succession and decline of all the six cusps, and do not require any new hypothesis to explain their appearance. Dr. Rose supports his fusion hypothesis by a reference to the Multi- tuberculates (p. 403); he could hardly have made a more unfortunate choice, because between the little pauci - tubercular Microlestes of the upper triassic and the multi-tubercular Neoplagiaulax of the lower eocene we can follow the successive addition of tubercles with ease. I expect soon to demonstrate that the molars of this aberrant group were also of tritubercular, i. e. haplodont origin. 1) See the Memoirs of Owen and Osboen upon the mesozoic 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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