BRACHIOPODA — TELOTREMATA. 



33 



355. S. asper Hall. Devonic. 

 Small, subp\ ramidal. Pedicle valve with high, flat cardinal 



area, narrow del hyri.um and broad, shallow sinus, rapidly narrow- 

 ing'toward the beak. Fold low and rounded. Plications fine and 

 low. Whole surface granulose. 



Hamilton of New York, Illinois, Wisconsin, Iowa. 



356. S. (Delthyris) consobrinus d'Orbigny. (Fig. 422, a-b.) 



Devonic. 



Gibbous with pedicle valve the more convex and arcuate from 

 beak to front. Cardinal area elevated and concave. Sinus deep 

 and wide. Brachial valve with an abruptly elevated mesial fold 

 usually marked by a depression. Surface marked by 8 to 12 

 angular radial plications crossed by concentric lamellae. 



Hamilton of New York, Kentucky, Ohio, Wisconsin. 



a, b 



Fig. 422. a-b, Spirifer {Delthyris) consobrinus ; c-d, S. {Delthyris) sculptilis ; e, 

 Spirifer tullius (Pal. N. Y., IV.). 



357. S. (Delthyris) sculptilis Hall. (Fig. 422, c-d.) Devonic. 



Gibbous. Hinge line prolonged into mucronate extensions. 

 Length of shell about half the width on the hinge line. Surface 

 strongly marked by 3 to 5 strong plications on each side of the 

 fold and sinus, leaving a somewhat wide space at the cardinal ex- 

 tremities marked only by the concentric striae which cross the 

 whole shell as strong imbricating lamellae. 



Hamilton of New York, Pennsylvania, Kentucky, Indiana, On- 

 tario. 



