APPENDIX E. — PALAEONTOLOGY. 181 



The only specimen of this species collected by the expedition is rather 

 too imperfect to permit us to make a satisfactory description. It was 

 found in the cretaceous strata at Camp No. 4, Cross-Timbers, Texas. 



CARDruM muxtistriatum, Shumard. 

 Paleontology, PL 4, fig. 2. 



Shell sub-rotund, inflated, length and breadth nearly equal, truncated 

 posteriorly, basal and anterior margins rounded; surface of posterior 

 sub-margin with from fourteen to fifteen regular radiating striae ; remain- 

 der of surface marked with fine, equal, rounded, close, concentric striae. 

 Beaks rather prominent. 



This is a neat, pretty species ; and it is to be regretted that the speci- 

 mens collected were not in a better state of preservation. It was found 

 at encampment No. 4, Cross-Timbers, Texas, where it is rather un- 

 common. 



Panop^ea texana, Shumard. 

 Paleontology, PI. 6, fig. 1. 



Shell oval, elongate, inflated anteriorly, compressed behind, beaks 

 moderately prominent, basal edge rounded, buccal extremity wide, 

 rounded; surface marked with irregular concentric slightly elevated 

 ribs. Length about 2 5-10 inches, breadth 1 4-10 inch, thickness 

 1-10 inch. 



The only specimen of this species brought home by the expedition is 

 an imperfect cast. 



Locality, encampment No. 4, Cross-Timbers, Texas. 



Terebratula choctawensis, Shumard. 



Paleontology, PI. 2, fig. a, b. 



Shell sub-globose, inflated, sub-pentagonal, front slightly truncated 

 surface minutely punctate, the puncti only visible when examined 

 through a strong lens ; dorsal valve most inflated ; beak obtuse, recurved, 

 pierced by an oval aperture ; area distinct, forming a well defined ob- 

 tuse angle ; ventral valve moderately convex, sub-orbicular. Length 9 

 lines, width 8 lines, thickness 6£ lines. 



