254 PALjEONTOLOGY OF NEW YORK 



1874. Streptorhynchiis, Hartt. Bull. Buffalo Soc. Nat. Sci., vol. i, v- 248, pi. ix. 



1874. StreptorJiynchtis, Derby. Carbonif. Brachiopoda of Itaitdba, p. 37, pis. v, viii. 



1874. StreptorhyncJius, Nichouson. Paleontology Piovincc of Ontario, p. 70. 



1875. Heinipronitcs, Mkbk. Paloeontology of Ohio, vol. ii, p. 279, pi. x, fig. 5. 



1877. Hemiprimltes, Meek. Geol. Expl. Fortieth Parallel, vol iv, p. 35, pi. iii, fig. 2; p. 62. pi. vii, tig. 2. 

 1877. Streptorhyncltus, Hall and Whitfield. Geol. Exploration Fortieth Parallel, vol. iv, p. 252, 



pi. iv, figs. 1-3. 

 (?) 1878. Streptorhyiichm, Dawson. Acadian Geology, Third Edition, p. 296, fig. 96. 



1879. Streptorhynchtix, Hall. Twenty-eighth Kept. N. Y. State Mns. Nat. Hist., pp. 150, 151, pi. xxi, 



tigs. 26-33 ; pi. xxiii, tigs. 11-13. 

 1882. Streptorhynchus, Whitkikld. Annals N. Y. Academy of Sciences, vol. li, pp. 193, 200. 

 1882. Streptorhynchtui, Hall. Eleventh Kept. Indiana State Geologist, pp. 287, 288, pi. xxi, tigs. 26- 



33 ; pi. xxiii, figs. 11-13. 

 1SS3. yStrKptorhyncJms. Hall. Second Ann. Rept. N. Y. State Geologist, /.l. xxxix, tigs. 21-32; jil. xl, 



figs. 1-9 ; pi. xlii, figs. 16-27. 

 1884. Streplurhyiwhus, Walcott. Palfeonfology Eureka District, p. 117, pi. xiii, figs. 7, 16. 

 1884. Orthnlhetes. Wa.iqen. Salt-Range Fossils, I, vol. iv (fas. 3), p. 607, pi. Iv, figs. 1, 2. 

 1884. Orthothetes, Davidson. Genei-al Summary British Fo.ssil Brachiopoda, p. 379. 

 1887. Strepforhyiichiis, CEhlert. Etudes sur quelques Foss. Devon de I'Ouest de la France. 



1887. Strophomena, Foerste. Bull. Denison University, vol. ii, p. 105, pi. viii, tigs. 31, 32, 34-38. 



1888. Hemipronites, ilv,RR\CK. Bull. Denison University, vol. iii, p. 37, pi. iii, fig 24; pi. v, fig. 14 ; 



pi. vi, fig. 8; pi. ix, fig. 21 ; vol. iv, pi. ii, figs. 1, 5 ; pi. iii, fig. 12. 



1889. Streptorliynelaus, Beecher and Clarke. Memoirs N. Y. State Museum, vol. i No. 1. 



1889. Strcpturhyiwlms, Nettelrotii. Kentucky Fossil Shells, pp. 140-142, pi. xxix, tigs. 11, 12 ; 



pi. XXX!, figs. 31-33. 



Diagnosis. Shells plano-convex or biconvex, sometimes becoming concavo- 

 convex with age. Brachial valve usually the deeper in the pallial region ; 

 pedicle-valve liighest about the umbo, which is sometimes much extended, and 

 often shows a pronounced tendency to irregular growth. Surface covered with 

 slender, subequal radii, which are crenulated by sharp concentric striag. Hinge- 

 line long, equaling, and often greater than the width of the shell ; in some 

 species frequently showing a tendency to auriculation at the extremities. 

 Pedicle-valve with the cardinal area prominently developed ; the delthyrium 

 covered by a thick, more or less convex deltidium, which is rarely if ever per- 

 forated at maturity. On the interior the teeth are moderately large, sometimes 

 thickened, but not supported by dental plates. The muscular area is marked 

 by flabelliform cardinal scars, inclosing a small adductor impression; similar to 

 that in Rhipidomella, but often very faint. 



In the brachial valve the cardinal area is narrow, the deltidial covering 

 small and emarginate at the center. The cardinal process is united to the 

 crural plates, the wiiole forming a vertical subcrescentic process, most elevated 



