Descriptiuns of Species. 27 



ing. (See U. S. and Mexican boundary Report, vol. i, [>. 148, 

 plate iii. figs. 2a, b, c.) Occurs abundantly in the plant beds of 

 tlie Paluxy. The species is named for Professor G. W. Stolley, 

 of Austin, Texas, whose work as a collector is esteemed in both 

 Europe and America. 



Trigonia cieuulata lioemer. 



Plate III, Fig. 4. 



Roemer. Kreidebildun ;en von Texas, p. 51, plate vii, Hg. G. 



This species, described l)y Roemer from imperfect casts, may 

 l)e the same as T. stoliei/i. The specimen here figured was col- 

 lected from the bluffs of the Colorado near Bull creek, Travis 

 county. 



Chione (?) decepta sp. nov. 



Plate I, Figs. 9 and 10. 



Shell sul)-triangulate or elliptical in outline. com})ressed in 

 cross-section from base to umbonos ; umbones forward of center, 

 small, and touching each other ; lunular area small , cordate oval ; 

 ])allial margin widely rounding ; anterior cardinal margin con- 

 cave, shorter than ]josterit)r ; posterior cardinal margin long, 

 slightly convex, asymmetrical; cardinal mechanism not shown; 

 surface marked l:)y long concentric and very faint irregular lines, 

 anterior muscular scar elongate, rounded ; posterior muscular 

 impression flat, depressed at extreme posterior end. 



The casts of this form are al»undant throughout the Glen Rose 

 Ijcds, but its generic position is uncertain. It may possibly be- 

 long to the Cardltuhe. In the hills north of Lampasas, near 

 the top of the formation, the specimens occur in great abuutlance 

 with the shell preserved in calcite, showing the exterior structure. 

 Ct)nrad's species of Adaiie texaiui;^' described from a cast from 

 an unknown locality, has a su[)erficial resemblance to this form, 

 according to his descri[)ti()n and figures, Imt it is more triangular 

 and otherwise different, as seen by comparison with his type in 

 the National Museum. 



* U. S. and Mexican Boundary Report, vol. i, p. 152, plate v, fig. *J. 



