66 SYSTEMATIC PALEONTOLOGY 



Thecachampsa (?) sicARiA Cope. 

 Plate XXVII, Figs. 3, 4, 5. 



Thecachampsa sicaria Cope, 1869, Proc. Acad. Nat. Sci. Phila., vol. xxi, p. 12. 



Thecachampsa sicaria Cope, 1869, Amer. Nat., voL iii, p. 91. 



Thecachampsa sicaria Cope, 1871, Trans. Amer. Philos. Soc, vol. xiv, pp. 63, 64, pi. 



V, figs. 6, 6a, 6b. (Pp. 1-104 appeared in 1869.) 

 Thecachampsa [Crocodilus) sicaria Cope, 1882, Amer. Nat., vol. xvi, p. 984. 



Description. — Described from teeth " with much compressed crowns 

 of the tooth with prominent cutting edges." The specimens were 

 loaned to Cope by Mr. P. T. Tyson, the State Geologist of Maryland. 



Occurrence. — St. Mary's ( ?) Formation. " Near the mouth of the 

 Patuxent Eiver." 



Collection. — Not known. 



Thecachampsa ( ?) contusor Cope. 

 Plate XXVII, Figs. 6a, 6b. 



Thecachampsa contusor Cope, 1867, Proc. Acad. Nat. Sci. Phila., vol. xix, p. 143. 

 Thecachampsa contusor Case, 1901, Md. Geol. Survey, p. 96, pi. x, fig. 4. 

 Crocodylus antiqutis Hay, 1902, Bull. 179, U. S. Geol. Survey, p. 512. (In part.) 



Description. — This species is of very doubtful value, it probably be- 

 longs with Th. antiqua. It was described from a single tooth, " re- 

 markable for its short conic form. The basis is circular, and its diam- 

 eter is three-fifth the length of the tooth. The apex is rather acute 

 and circular in section, it is directed to one side, and the tooth is 

 •slightly flattened on the inside of the curve. This face is bounded by 

 a low obtuse ridge on each side, for the basal two-thirds of the crown, 

 which are not distinguishable from a series of ridges which mark, at a 

 distance of a line, the basal three-fifths of the crown; they are less dis- 

 tinct on the convex aspect, and are separated by concave surfaces. 

 Instead of the cutting ridges of Crocodilus, the apex is provided with 

 a narrow flattened plane on each side. The surface of this portion and 

 much of the convex, is marked by a minute decussation or chevroned 

 structure. 



"Vertical length 14.5 lines (29 mm.); diameter of the base of the 

 crown 8.5 lines (17 mm.)." 



Cope says in Trans. Amer Philos. Soc, vol. xiv, 1871, p. 64: "The 



