690 



BRACHIOPODA. 



| xrc- pol. 



muscular area, from which radiate a 

 series of vascular ridges and depres- 

 sions ; the strongly marked pair of ad- 

 ductors are situated posteriorly, just 

 within this muscular area; lying in 

 front of these is a single (rarely divided) 

 elongate adductor impression which 

 often extends forward to the center of 

 the shell ; on each side of the muscular 

 impressions is a thickened triangular 

 area, very narrow at its origin in the 

 umbonal region, widening anteriorly 

 and produced into two divergent fur- 

 rows (four in all), which extend over the 

 pallial region, in some instances almost 

 to the anterior margin. In the brachial 

 valve there are two short, divergent, 

 mm] plates, which are not united at 

 their bases to form a hinge plate, as 

 in Rensselseria ; a low median ridge 

 arises between them, passing for a short 

 distance along the bottom of the valve, 

 separating the obovate, narrowly rlabel- 

 liform muscular scars of the adductor 

 muscles. These scars are characterized 

 by the strong striation of their surfaces; 

 surface smooth, or with obscure radi- 

 ating stria;; distinguished from Rens- 

 selteria, which has strong radiating 

 stria- on the surface, and preserves two 

 broad, strong, dental plates on the inte- 

 rior of the pedicel-valve, which reach 

 nearly to the bottom of the rostral and 

 post umbonal cavity, leaving a narrow 

 space for the muscular area, quite un- 

 like that of the corresponding valve of 

 Newberria. It is from this narrow cav- 

 ity, produced by the encroachment of 

 these strong dental plates, that we have 

 the narrow rostral casts of Rensselaria. 

 The thickened strong hinge-plate, which 

 supports the crura in the brachial valve 

 of Rensselseria, does not exist in New 

 herria ; the spoon-shaped process found 

 in Amphigenia does not exist in New- 

 berria. Type N. johanni. 



condoni, McChesney, 1867, (Rensseheria 

 condoni,) Trans. Chi. Acad. Sci., vol.1, 

 p. 36, Oriskany Or. 



claypolei, Hall, 1891, Advance Sheets 

 10th Ann. Rep. N. Y. St. Geo., Ham. 

 Gr. 



johanni, Hall, 1867, (Renssela'ria johanni,) 

 Pal. N. Y., vol. 4, p. 385, Up. Held. Gr. 



lsevis, Meek, 1868, (Rensseheria kevis,) 

 Tians. Chi. Acad. Sci., p. 108, Devonian. 



missouriensis, Swallow, 1891, Advance 

 Sheets 10th Ann. Rep. N. Y. St. Geo., 

 Ham. Gr. 

 Nucleospira indianensis, S. A. Miller, 1891, 

 Advance Sheets 17th Rep. Geo. Sur. 

 Ind., p. 79, Ham. Gr. 

 Obolella misera and O. pretiosa, refer to 



the genus Linnarssonia. 

 Oehlertella, Hall, 1892, Pal. N. Y., vol. 8, 

 p. 132. A proposed subgeneric name 

 to include Discina pleurites. 

 Orbiculoidea herzeri, Cuyahoga Shales, 

 O. numulus, Low. Held. Gr., and 



O. ovalis, Trenton Gr., Hall, 1892, Pal. 

 N. Y., vol. 8, pp. 177, 178. 

 Orthis arcuaria, Hud. Riv. Gr. ; 0. holstoni, 

 O. loricula, O. saffordi, Trenton Gr. ; 

 O. oweni, Keokuk Gr. ; O. senecta, 

 Clinton Gr., and O. superstes, Chemung 

 Gr., Hall, 1S92, Pal. N. Y., vol. 8, pp. 

 340 to 342. 



benedicti, S. A. Miller, Advance Sheets 

 17th Rep. Geo. Sur. Ind., p. 78, Ni- 

 agara Gr. 



germaiid, Winchell & Schuchert, 1892, 

 Am. Geo., vol. 9, p. 290, Galena Gr. ; 

 metdri, Trenton Gr. ; pronrila, Hud. 

 Riv. (ir. Not defined so as to be recog- 

 nized. 



goodwini, Nettleroth, 1889, Kentucky 

 Foss. Shells, p. 39, Up. Held, or 

 Ham. Gr. 



integualis. Bee Streptorhynchus ina-quale. 



linnevi, Nettleroth, L889, Kentuckv Foss. 

 Shells, p. 41, Hud. Riv. Gr. 



manitobensis, Whiteaves, 1892, Cont. to 

 Can. Pal., p. 283, Devonian. 



missouriensis, Swallow, is the same de- 

 scribed afterward as O. theimii. 



CQrpulenta, macrior, rogata, tersus, min- 

 nesotensis, petroe, Sardeson, 18 { .»2, Bull. 

 Minn. Acad. Nat. Sci., vol. 3. pp. 330, 

 382, Trenton «fc Hud. Riv. Gr. The first 

 four seem to be synonyms for O. testu- 

 dinaria, but possibly they are not. 

 Orthirina alberta, Walcott. 1888, Proc. U. S. 

 Nat. Mus., p. 442, Up. Taconic. Not 

 properly defined. 

 Palerina is a generic name proposed for 

 such shells as Kutorgina labradorica, 

 without any distinct generic characters 

 being pointed out. See Am. Jour. Sci. 

 and Arts, Ser. 3, vol. 41, p. 34:!. 

 Pentamkreli.a thusnelda, Nettleroth, 1889, 

 Kentuckv Foss. Shells, p. 51, Up. 

 Held. Gr. 

 Pentamerus colletti, S. A. Miller, 1891, Ad- 

 vance Sheets 17th Rep. (ieo. Sur. Ind., 

 p. 77, Waterlime Gr. 



complanatus, Nettleroth, 1889, Kentucky 

 Foss. Shells, p. 53, Niagara dr. 



decussatus, Whiteaves, 1891, Can. Record 

 Sci., p. 295, Up. Sil. 



globulosus, Nettleroth, 1889, Kentucky 

 Foss. Shells, p. 54, Niagara Gr. 



knotti, Nettleroth, 1889, Kentucky Foss. 

 Shells, p. 56, Niagara Gr. 



uniplicatus, Nettleroth, 1889, Kentucky 

 Foss. Shells, p. 63, Niagara Gr. 

 Pholidops calceola, P. patina, Hall, 1892, 

 Pal. N. Y., vol. 8, p. 182, Corniferous 

 limestone. 

 Polyto'chia. Hall, 1892, Pal. N. Y., vol. 8, 

 p. 239 [Fty. polm, many ; toichoa, the 

 wall of a house.] Shell small, subtri- 

 hedral in contour; hinge-line straight; 

 pedicel-valve with a high, nearly verti- 

 cal cardinal area, obliquely striated ; 

 delthyrium covered with a convex 

 plate ; dental lamellae widely separated, 

 descend for a distance vertically, and 

 then bend inward to the median line, 



