Description
Original diagnose after Leidy (1877) p. 252: While engaged in describing some unusual forms of the teeth of Sharks, I take the opportunity of noticing another from the marls of New Jersey. The teeth to which I refer arc probably symphysial, but their relationship with lateral associates remains undetermined. The museum of the Academy contains twelve of these teeth, of which six are from Vincenttown, presented by Col. T. M. Bryan; four from Monmouth Co., presented by Dr. P. Knieskern; one from Burlington Co., presented by Dr. C. C. Abbott; and one from Allowaystown, presented by Dr. H. C. Yarrow. The teeth have the general appearance of those of Lamna laterally compressed. The crown of the tooth usually, as represented in figures 25-28, Plate xxxiv., has a sigmoid sabre-like form with the anterior bonier sharp and the posterior border obtuse. The root has the construction of that of a Lamna tooth, but the two sides appear pressed towards each other•, so that the processes are directed obliquely and parallel. In some teeth, as in figure 27, the processes are nearly or quite equal; in other teeth, as in figures 25, 26, one process is shorter ihan the other. Figures 29 and 30 represent. transitional forms from that nbove indicated to the more ordinary one of Lamna teeth. In one of these, fig. 29, the crown is sharp a short distance below the point on the outer border, as it is the entire length along the inner border; in that of fig. 30 the crown is sharp along both • borders. The root in both teeth is not laterally compressed, but has nearly the common form seen in most teeth of Sharks.

Remarks
shark-references Species-ID=7535;

References