ACTINOPTERI. 147 



elongated, bean-shaped, slightly concave in front and convex 

 behind, and slightly wider externally than internally. Length of 

 tooth about 20 mm. (From Leidy.) 



The above paratype, figured by Leidy, differs from his type in 

 not having small lateral teeth in at least one series each side 

 of the median, and on one side traces of a second series. 



Formation and locality. Originally from the Cretaceous of 

 Mississippi, but also known from Leidy's record of the above- 

 described example from the greensand marl of Crosswicks in 



Fig. 90. — Pycnodus phaseolus Hay. (Type, from Leidy.) 



Burlington County (J. H. Slack). This example was said to 

 have been in the collection of the Academy, but I have not located 

 it. [A marly clay, the Merchantville formation, outcrops at 

 Crosswicks village, but no true marl beds occur within several 

 miles of that place. The Navesink marl was formerly dug along 

 Crosswicks Creek, south of Wain ford, and 6 or 7 miles above 

 Crosswicks village. It is impossible to determine whether the 

 specimen is referable to the Merchantville clay or to the Nave- 

 sink marl, probably the latter, K.] 



Pycnodus bobustus Leidy. 



Pycnodus robustus Leidy, Proc. Acad. Nat. Sci. Phila., 1857, p. 168. Green- 

 sand of New Jersey. 

 Leidy, Rep. U. S. Geol. Surv. Terr., I, 1873, pp. 293, 350, PI. 37, figs. 

 18-19 (type). 



Tooth elongate, rather depressed, slightly convex anteriorly as 

 viewed above, with either end very slightly tapering and rounded. 

 Edges all rounded and like surface smooth. Viewed below 



