NO. 2 BRACHIOPOD SUPERFAMILY STENOSCISMATACEA GRANT 93 





;2ww 



H I J 



Fig. 19. — Cyrolexis haquei n. sp., Lower Productus Limestone, Salt Range; 

 transverse sections X4, cut perpendicular to commissure, USNM 142065, original 

 length 12.9 mm., distances from pedicle valve beak. 



A. 0.9 mm. : no intercamarophorial plate. B. 1.1 mm. : thick filling between 

 hinge plate and camarophorium, edges of camarophorium meet hinge plate, car- 

 dinal process high. C. 1.3 mm. : small dot of shell at locus of intercamarophorial 

 plate. D. 1.6 mm.: camarophorium separating from crura. E. 1.8 mm.: crura 

 separate from camarophorium. F. 1.9 mm.: crura thinner, divergent. G. 2.2 

 mm. : crura separated widely, near edges of spondylium. H. 2.4 mm. : crura 

 gone ; wide overlap of valves. I. 2.8 mm. : spondylium nearly gone. J. 3.5 mm. : 

 septum of camarophorium separated from valve floor; wide overlap of valve 

 edges. Camarophorium disappears at 4.5 mm. 



line, weaker and fewer costae that begin farther forward, and its 

 shorter and more strongly curved pedicle beak. 



Of the species compared above, only C. superstes is represented by 

 Russian specimens in the U.S. National Museum collections. These 

 specimens, ten in number, show the generic characters of Cyrolexis, 

 and undoubtedly belong to that genus. They have the pedicle beak 

 tightly curved onto the brachial umbonal region completely closing 

 the foramen; the brachial valve strongly overlaps the posterolateral 

 edges of the pedicle valve ; costation is weak, and the stolidium is ab- 



