. Bulletin of the British Museum (Natural History), Geology. 32 UPPER EOCENE MAMMALIA The four molars form a continuous series internally, the hypoconulid of one molar fitting closely against the external cingulum of the adjacent posterior tooth. M1-M3 are subequal in size; M4 is of similar length but with a narrower talonid. M4 is rectangular in outline with subequal talonid and trigonid. The trigonid is only moderately elevated, the posterior wall falling steeply to the basined talonid. The protoconid is the largest cusp, the metaconid intermediate and the paraconid smallest. There is a prom
. Bulletin of the British Museum (Natural History), Geology. 32 UPPER EOCENE MAMMALIA The four molars form a continuous series internally, the hypoconulid of one molar fitting closely against the external cingulum of the adjacent posterior tooth. M1-M3 are subequal in size; M4 is of similar length but with a narrower talonid. M4 is rectangular in outline with subequal talonid and trigonid. The trigonid is only moderately elevated, the posterior wall falling steeply to the basined talonid. The protoconid is the largest cusp, the metaconid intermediate and the paraconid smallest. There is a prominent antero-external cingulum. The paraconid, which forms the sharp antero-internal extremity of the tooth, is strongly internal, lying on an antero- posterior line with the metaconid and entoconid; it is completely separated from the metaconid. The deeply-basined talonid bears a subequal hypoconid and entoconid and a smaller hjrpoconulid; this hypoconulid is intermediate between the median and internal positions and posterior to the hypoconid and entoconid. A small antero-posterior crest runs from the entoconid to the posterior trigonid wall from which it is separated by a small valley. Similar crests connect the hypoconulid to the hypoconid and entoconid. There is a small crista obliqua. A strong antero- external cingulum is pressed up against and external to the projecting hypoconulid of the anterior tooth; it runs below the protoconid and hypoconid, to the base of the hypoconulid. M3 is structurally almost identical with M4, except that the tooth is somewhat wider transversely. M2 is structurally nearly identical with M3. Mi is similar but a little smaller in size. P3 bears a prominent single anterior cusp which is crested anteriorly. Posteriorly two crests fall from the cusp to a small internally-shifted talonid. P2 is smaller but structurally very similar to P3 and separated from it by a marked diastema. Pi is separated from P2 by a small diastema; the tooth is represent
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