NO. 5 RHYNCHONELLOID BRACHIOPODS — COOPER 87 



Page 

 terior views of the holotype, X I, showing twisted anterior commis- 

 sure, U.S.N.M. 549386a. 16, Dorsal view of the holotype showing 

 smooth exterior, X J i- l 7, 18, Side and anterior views of the holo- 

 type, X 2, showing twisted commissure. 19, Posterior of the holotype, 

 X 3, showing deltidial plates and foramen. 20, 21, Posterior of another 

 specimen, X 4. showing short dental plates and cardinalia with falcifer 

 crura (see discussion), paratype U.S.N.M. 549386b. 



Eocene, deep cut north of Grua 9, Ramal Juan Criollo, Camaguey 

 Province, Cuba. 



C. Streptaria buchi (Michelotti) 38 



Figs. 22-31. 22-26, Respectively ventral, dorsal, anterior, side, and 

 posterior views of a complete specimen showing twisted anterior com- 

 missure, X I, hypotype U.S.N.M. 549352a. 27-29, Respectively ante- 

 rior, dorsal, and side views of the preceding specimen, X 2, showing 

 twisted commissure. 30, Posterior of the same specimen, X 3i show- 

 ing large foramen with elevated rim. 31, Posterior of the brachial 

 valve of another specimen prepared to show the strong socket ridges, 

 wide outer hinge plates, and falcifer crura with thickened ventral 

 edge, X 6, hypotype U.S.N.M. 549352b. 



Middle Miocene, Messina, Sicily. 



Plate 20 



Eohemithyris 



A. Eohemithyris alexi Hertlein and Grant 30 



Figs. 1-16. 1-5, Respectively dorsal, posterior, ventral, side, and ante- 

 rior views of a complete and undistorted specimen, showing form and 

 true profile of valves, X 1, hypotype U.C.M.P. 15524- 6-9, Respec- 

 tively, anterior, ventral, dorsal, and side views of the same specimen, 

 X 2. 10, Dorsal view of another nearly perfect specimen showing 

 rounded outlines and low fold, X 1, hypotype U.C.M.P. 15526. 1 1, 

 Posterior of the same specimen, X 3, showing small foramen. 12, 

 Posterior of another specimen, X 3, showing small foramen and con- 

 junct deltidial plates, hypotype U.C.M.P. I554 1 - *3, *4, Dorsal and 

 ventral views of a specimen from which the shell has been scraped to 

 show the muscle fields, X 2, hypotype U.C.M.P. 15542. 15, 16, Full 

 view and partial side view of the cardinalia, X 6, showing narrow 

 outer hinge plates and broad, long falcifer crura, hypotype U.C.M.P. 



15545- 



Eocene (Domengine formation), from just below the 1/4 section 

 marker toward the top of the 25-foot last sandstone "reef" on the ridge 

 on the east side of the North Fork of Media Agua Creek, grid, 

 coord. 142001-139004, McKittrick (15') Quadrangle, Kern County, 

 California (see text for further information). 



B. Eohemithyris grayi (Woodward) 33 



Figs. 17-23. 17, Dorsal view of the exterior, ca. X 2, showing anterior 

 costae and minute foramen, holotype British Museum (Nat. Hist.) 

 ZB280. Specimen coated by ammonium chloride. 18-20, Respectively 



