82 PALEONTOLOGY OF ILLINOIS. 



VATICINODUS VETUSTUS, St. J. and W. 



PI. III. Fin. 1. 



The unique example of the present species represents a large pos- 

 terior tooth belonging to the left ramus of the upper jaw. It is 

 elliptical or spatulate in general outline, moderately arched longi- 

 tudinally, and apparently strongly inrolled along the outer margin, 

 terminating posteriorly in a sharply-rounded angle formed by the 

 posterior basal spur, which extends conspicuously beyond the coronal 

 limits, angle of obliquity of the antero-lateral border not shown, but 

 evidently forward from the inner angle. The tooth is considerably 

 thickened in the region of the posterior border, its substance rapidly 

 diminishing in the opposite direction, on account of which the ante- 

 rior articular border is liable to mutilation, as is the case in the 

 present example. The basal rim along the postero-lateral border 

 forms a prominent platform projecting beyond the coronal border for 

 half the distance toward the point of inrollment, the coronal enamel 

 forming a heavy rounded inbeveled belt distinctly defined from the 

 basal portion, which latter also forms a deep border along the inner 

 margin of the tooth. Inferior surface marked by interrupted coarse 

 verrucose stri, conforming in direction to that of the inrollment of 

 the tooth. The crown still retains along the inner margin the orig- 

 inal coating of glossy enamel, the summit and outer region exhibit- 

 ing progressive degrees of wear from use, and fine punctate structure, 

 inner margin distinctly defined from the base by the limits of the 

 enamel coating, and marked by parallel lines of growth; posterior 

 prominence occupying perhaps one-third the lateral diameter of the 

 crown, presenting a broad, low convexity flattened along the crest 

 and somewhat depressed from within outwards, where it merges into 

 the border anterior area, which latter is smooth and without longi- 

 tudinal folds. From the surface conformation, and direction of in- 

 rollment, it is safe to infer the somewhat oblique outward and for- 

 ward course of the antero-lateral border. Greatest length of crown 

 probably near 13 centimetres, to extremity of posterior spur 15 cen- 

 timeters, greatest breadth near middle of tooth along a line diagonal 

 to the longitudinal axis 45 m m. 



The mutilated condition of the sole example representing the spe- 

 cies does not allow the making out of the character of the antero- 

 lateral border; otherwise the specimen permits of satisfactory com- 

 parison with allied congeneric teeth. Of the latter there appears to 



