BRACHIOPODA — TELOTREMATA. 



349 



CXVII. Nucleospira Hall. 



Small, subcircular, gibbous. Hinge line short. Valves nearly 



equal. Beak of pedicle valve slightly extended beyond that of 



opposite valve. Brachial valve with a large, hook- like cardinal 



process curved sharply posteriorly. Crura long and straight. A 



% $ ^ 



Fig. 453. Nucleospira pisiformis. (After Hall.) 



conspicuous median septum extends from beak to front in each 

 valve. Surface in perfect specimens covered with numerous 

 slender spines ; these are usually worn off. 

 Siluric-Lower Carbonic. 



403. N. pisiformis Hall. (Fig. 453.) Siluric. 

 Small. Each valve bears a slight depression down the center. 



Surface marked with fine concentric striae. 



Niagaran of New York, Kentucky, Indiana, Missouri. 



404. N. concinna Hall. (Fig. 454.) Devonic. 

 Depressed spheroidal. Surface smooth, very finely papillose or 



when perfect covered with very fine spines. 



Onondaga-Hamilton of New York, Pennsylvania, Virginia, 

 Ohio, Kentucky, Indiana, Nevada, Ontario. 



Fig. 454. Nucleospira coitcinna (Pal. N. Y., IV.). 



CXVIII. Anoplotheca Sandberger (emend. Hall and Clarke). 



Pedicle valve convex, with incurved umbo. Brachial valve 

 concave or flat, more rarely convex, with a high median septum. 

 No cardinal area. Plications few, crossed by fine concentric 

 growth lines, making the surface rough. Siluric-Devonic. 



A. Shell large, over ]/ 2 inch wide 408. A. Jla belli tes. 



B. Shell small, much less than y 2 inch wide *, 



* Brachial valve concave 407. A. concava. 



* Brachial valve flat or convex I. 



I. Hinge line straight 405. A. heviispherica. 



I. Hinge line curved 406. A. plicatula. 



