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NEW BRACHIOPODS 

 By G. ARTHUR COOPER 



Assistant Curator, Ditnsion of Stratigraphic Paleontology, 

 US. National Museum 



(With Two Plates) 



One of the most profitable realms for the collection of brachiopods 

 living in the waters of the Atlantic Ocean is the region about the 

 West Indies. From this region i6 species of brachiopods, repre- 

 senting lo genera, are known. Of this number the Johnson-Smith- 

 sonian Deep-Sea Expedition collected six species, representing six 

 genera, some of them the rarest and most interesting brachiopods 

 of the region. The following species have been identified : Dallina 

 floridajia (Pourtales), Thecidellina barretti (Davidson), Platidia 

 " seminula," Gryphus bartlettii (Dall), Argyrotheca harrettiana 

 (Davidson) and Terehratulina species. Two additional species have 

 proved to be new and are here named in honor of the distinguished 

 leaders of the expedition. 



GRYPHUS BARTSCHI, n. sp. 



Plate I, figs. 1-8 



Gryphus cubensis Dall (in part), Proc. U.S. Nat. Mus., vol. 57, p. 315, 1920; 

 U.S.N.M. nos. 193567, 226290, 64250, 211014, 64264 (part), 274140 (part). 

 Gryphus bartlettii Dall (in part), idem, p. 314, 1920; U.S.N.M. no. 64258. 



Shell moderately large for the genus, longitudinally oval in outline. 

 Hinge narrow. Lateral profile unequally biconvex, the ventral valve 

 having the greater depth. Lateral commissure nearly straight ; an- 

 terior commissure rectimarginate or faintly uniplicate. Beak slightly 

 incurved, foramen mesothyrid to permesothyrid, labiate. Surface 

 marked by fine concentric lines of growth and faint, distant, elevated 

 radial lines. 



Ventral valve rather strongly convex, most convex a little pos- 

 terior to the middle of the shell ; anterior portion flattened ; anterior 

 margin gently rounded or subtruncate. 



Smithsonian Miscellaneous Collections, Vol. 91, No. 10 



