NO. 2177. FOSSIL FISHES IN NATIONAL MUSEUM— EASTMAN. 255 



the smooth beveled edge, set with many minute spines directed upward; these spines 

 cover the antero-lateral edges of the base of the principal cone. Median cone conical, 

 somewhat curved backward, rapidly tapering to an acute point; lower portion with 

 a nearly circular section, finely and evenly striated longitudinally, near the point 

 smooth, compressed, with cutting edges; lateral denticles 6-7 on either side, conical, 

 striated and curved backward, exterior pair much larger than intermediate ones. 



Formation and locality. — St. Louis limestone, Missouri. 



CLADODUS ACULEATUS, new species. 



Plate 10, fig. 4; plate 18, fig. 1. 



Teeth small, the crown consisting of a long, slender, erect, and 

 pointed median cone, with faint longitudinal striae, and a pair of 

 similar lateral cones rising to about half the height of the principal cone, 

 only shghtly divergent, and all three with slight sigmoidal curvature. 

 Root short, not very deep. 



The teeth in this species are of relatively small size and gracefidly 

 formed. They agree more nearly in general form with O. gracilis 

 Newberry and Worthen, from the Coal Measures of Indiana, but are 

 distinguished from this and from other known species by the greater 

 height of the lateral denticles and their closer approximation to the 

 principal median cone, which is extremely slender from base to apex. 

 In the specimen selected as type (Cat. No. 8106, U.S.N.M.) of the new 

 species, the total height is only about 11 mm., and a second speci- 

 men in the same collection is still smaller. 



The two known specimens which have been obtained of this species 

 are each contained in small black concretions found in the Caney shale 

 of Antlers Quadrangle, Oklahoma, the exact locality being that 

 referred to as No. 3987 in Doctor Girty's paper on the Fauna of the 

 Caney Shale of Oklahoma.* An extensive collection of fossiliferous 

 nodules from this and other localities in the same region was made 

 by Doctor Girty, and is now preserved in the United States National 

 Museum. Comparatively few of these concretions contam fish re- 

 mains, but among them are several interesting forms, such as spines 

 of Stethacanthus, arthrodiran body plates, and small Palaeoniscids 

 showing the internal structure of the head. Two Coccosteus-like 

 antero-ventro-lateral plates are shown in plate 10, figures 5 and 6. 

 These remains are noticed hereinafter. 



The only mention that has previously been made of the occurrence 

 of fish remains in the Caney shale is to be found in Doctor Girty's 

 discussion of the famia in Bulletin 377 of the Geological Survey. The 

 author there remarks (p. 13): 



Another neglected type is the fishes, represented not only by teeth but by what 

 appear to be fragments of bone. In this connection may be mentioned agglomera- 

 tions of organic fragments, possible of coprolitic origin, which occur as a rule in small 

 concretions. 



» Bull, U. S. Geol. Surv., No. 377, 1909, p. 75. 



