Systematic Catalogue of Vertebrata of the Eocene of New Mexico; Collected in 1874

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1875 edition. Excerpt: ...jaw, .020; ledges not prominent index Small, last molar, .010; jaw, .014 major Small, last molar, .010; jaw, .0125 angustidens Smallest, last molar, .0085; jaw, .0135 procyoninus Superior molars. Neither external nor internal cingulum of the crown?species. External but no internal cingulum procyoninus. External and internal cingula present, but the internal weak... major et vasacciensis. External and internal cingula very strong, enamel rough. Larger, outer cusps flattened. agilis Least species, outer cusps conic and well separated... cuspidatus It is evident from the above tables that I am not certainly acquainted with the superior molars of O. tapirinus, O. index, and O. angustidens, nor with the mandibular teeth of O. cuspidatus. I have, however, numerous teeth which are not associated with those of the opposing series, and which doubtless cover nearly the entire ground of comparisons. Orohippus Tapirinus, Cope, sp. nov. Represented by mandibles with teeth of five individuals, which exceed in size those of the species heretofore known, being larger than the smaller Hyrachyi. The opposite cusps of the molars are not separated by so deep a notch as in some of the other species, while the oblique ridges extending forward from the outer tubercles are well developed. The same is true of the ridge which extends from the prominent heel of the last molar. The anterior ledge is horizontal, and is bounded by a ridge which descends from the anterior external tubercle and becomes transverse. It is less marked in all the other species. Enamel uearly smooth. The external cingulutn is very faint on the last molar, but becomes more distinct on the anterior; none on the inner side. Measurements. M. Length of bases of last two molars, (No. 1) 025 Length of bas