504 



University of Kansas Geological Survey. 



Outline Classification of Fort Pierre Species. 



MOLLTJSCA. 



Pelecypoda. 

 Aviculidae. 

 Avicula. 



Avicula fibrosa. 

 Inoceramus. 



Inoceramus cripsii. 

 Inoceramus incurvus. 

 Inoceramus sagensis. 

 Inoceramus altus. 

 Lucinidae. « 



Lucina. 



Lucina occidentalis. 



Gastropoda. 

 Aporrhaidse. 

 Anchura. 



1 Anchura sublsevis. 

 Cephalopoda. 

 Lytoceratidas. 

 Baculites. 



Baculites ovatus. 

 Stephanoceratidee. 

 Scaphites. 



Scaphites nodosns. 

 Turrilitidse. 

 Heteroceras. 



1 Heteroceras cochleatum. 

 ? Heteroceras angulatum. 



Inoceramus cripsii, var. barabina, Morton. Plate cix, fig. 2. 



Inoceramus barabina Morton, 1854, Stn. Org. Rem. 62, pi. xvn, f. 3. 

 Inoceramus gibbus Tuomey, 1854, Proc. Acad. Nat. Sci. Phil., vii, 170. 

 Inoceramus cuneatus M. & H., 1860, ibid. 181. 



Inoceramus cripsii, var. barabina, Meek, 1876, U. S. Geol. Surv. Terr., vol. 

 ix, pp. 49, 50, pi. xiii, ff. la, b, c; and pi. xn, f. 3. 



Meek's description: "Shell transversely ovate, moderately 

 gibbous in the anterior and umbonal region and cuneate pos- 

 teriorly, very nearly or quite equivalve, rather thin ; anterior 

 margin descending from the beaks, at first almost at right 

 angles to the hinge, after which it gradually curves obliquely 

 backward and downward, so as to pass by a graceful sweep into 

 the base ; posterior side long, compressed and rather regularly 

 rounded ; hinge long and straight, ventral margin forming 

 a broad semiovate curve ; beaks nearly terminal or located 

 directly over the anterior margin, rather prominent, but rising 

 little above the hinge, equal, oblique, somewhat incurved, and 

 nearly contiguous. Surface ornamented with moderately dis- 

 tinct, more or less regular concentric undulations. Length of 

 a large, rather long specimen, three and ninety-hundredths 

 inches ; height, two and seventy-five hundredths inches ; con- 

 vexity of both valves, two inches." 



In the summer of 1896, I collected some casts of young indi- 

 viduals of this species from shale thrown from a well a few 

 miles north of Atwood, in Rawlins county. There are also 

 some adult forms in the University collection, which were col- 



