﻿1052 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I27 



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 and interior views of a brachial valve, X 3, showing brachiophores and their 

 supports, paratype, 95876c; (12) posterior of another brachial valve showing 

 cardinal process, X 4, hypotype, 116863a; (13) pedicle interior, X 4, hypotype, 

 116863c 



Pogonip group (mottled zone 700 feet below the Eureka quartzite), base of the 

 first ridge east of Frenchman Flat, Las Vegas (i°) Quadrangle, Nev. 



B. Trematorthis tenuis Cooper, new species 342 



( 16-20) Brachial, side, pedicle, anterior, and posterior views, X 3, of the holotype, 

 117978a. 

 Horizon and locality same as preceding. 



C. Trematorthis robusta Cooper, new species 342 



(21-25) Respectively anterior, brachial, posterior, side, and pedicle views, X 4> of 

 the holotype, 116865a; (26) pedicle interior, X 4, paratype, 116865c; (27) same, 

 X 4, tilted to show the pseudodeltidium. 

 Horizon and locality same as preceding. 



Plate 30 

 Orthidiella, Orthidium 



A. Orthidium bellulum Ulrich and Cooper 340 



(1-5) Respectively posterior, pedicle, side, brachial, and anterior views, X 4, of 

 the holotype, 92848. 



Upper Pogonip group, Ikes Canyon, east side of Toquima Range, Roberts 

 Mountains (i°) Quadrangle, Nev. 



B. Orthidiella sp. 1 340 



(6-9) Anterior, pedicle, side, and brachial views of an unusually fasciculate indi- 

 vidual, X 2, figured specimen, 116861a; (10) posterior, X 3, of the preceding; 

 (11) interior of the brachial valve of a similarly marked specimen, X 3, figured 

 specimen, 116861b. 



Pogonip group (mottled zone 700 feet below the Eureka quartzite), base of 

 first ridge east of Frenchman Flat, Las Vegas (1°) Quadrangle, Nev. 



C. Orthidiella costellata Cooper, new species 338 



(12) Interior of the brachial valve, X 2, showing the cardinal process, paratype, 

 116859b; (13) exterior of a large pedicle valve showing the fine ornamentation, 

 X 1, paratype, n6859d; (14) interior of the pedicle valve, X 2, showing elongate 

 diductor muscle scars, paratype, 116859c; (15-17) pedicle, side, and brachial 

 views of a complete specimen, X 2, holotype, 116859a; (19) complete specimen 

 slightly turned to the side to show the cardinal process in position, X 4, paratype, 

 116859c. 



Pogonip group {Orthidiella zone), in the narrows 2 miles up Whiterock 

 Canyon, Roberts Mountains (i°) Quadrangle, Nev. 



(18) Orthidiella cf. O. costellata Cooper, new species. Brachial view of a large 

 complete specimen, X 2, figured specimen, 117981a. 



Pogonip group (mottled zone 700 feet below the Eureka quartzite), base of 

 first ridge east of Frenchman Flat, Las Vegas (i°) Quadrangle, Nev. 



D. Orthidiella longzvelli Ulrich and Cooper 339 



(20) Posterior of the brachial valve showing the cardinal process, X 4, holotype, 

 91299. 



Horizon and locality same as preceding. 



E. Orthidiella extensa Ulrich and Cooper 339 



(21-24) Brachial, side, pedicle, and anterior views of a nearly perfect specimen, 

 X 2, hypotype, n6857f; (26) same, Xi; (27) posterior view of same, X 3, 



