468 



LAMELLIBRANCHIATA. 



[AVI. CAR. 



scabridus, Hall, 1883, Pal. N. Y., vol. 5, pt. 

 1, p. 7, Ham. Gr. 



signatus, Hall, 1843, (Avicula signata,) 

 Geo. Rep. 4th Dist. N. Y., p. 265, and Pal. 

 N. Y., vol. 5, pt. 1, p. 29, Chemung Gr. 



simplex, Dawson, 1868, Acad. Geol., p. 

 306, Carboniferous. 



^spinuliferus, Meek & Worthen, 1870, 

 Proc. Acad. Nat. Sci., p. 39, and Geo. 

 Sur. 111., vol. 8, p. 116, Keokuk Gr. 



squama, Hall, 1883, Pal. N. Y., vol. 5, pt. 

 1, p. 27, Chemung Gr. 



striatus, Hall, 1843, (Pecten striatus,) Geo. 

 Rep. 4th Dist. N. Y., p. 264, and Pal. 

 N. Y., vol. 5, pt. 1, p. 22, Chemung Gr. 



.gubcancellatus, Hall, 1883, syn. for A. can- 

 cellatus. 



subrectus, Hall, 1852, (Avicula subrecta,) 

 Pal. N. Y., vol. 2, p. 331, Coralline lime- 

 stone. 



italboti, Worthen, 1884, Bull. No. 2, 111. 

 St. Mus. Nat. Hist., p. 21, St. Louis Gr. 



tenuicostus, Winchell, 1863, Proc. Acad. 

 Nat. Sci., p. 10, Marshall Gr. 



tenuis, Hall, 1883, Pal. N.- Y., vol. 5, pt. 1, 

 p. 39, Up. Chemung Gr. 



terminals, Hall, 1883, (Pterinopecten ter- 

 rainalis,) Pal. N. Y., vol. 5, pt. 1, p. 32, 

 Up. Held. Gr. 



unionensis, Worthen, 1875, Geo. Sur. 111., 

 vol. 6, p. 511, Corniferous Gr. 



utahensis, Meek, 1860, (Pecten utahensis,) 

 Proc. Acad. Nat. Sci., p. 310, Coal Meas. 



varsoviensis, Worthen, 1883, Geo. Sur. 111., 

 vol. 7, p. 321, Keokuk Gr. 



weberensis, Hall & Whitfield, 1877, U. S. 

 Geo. Sur., 40th parallel, vol. 4, p. 273, 

 Coal Meas. 



whitii, Meek, 1872, Pal. E. Neb., p. 195, 

 Coal Meas. 



williamsi, Meek, 1871, Proc. Acad. Nat. 

 Sci., p. 178, Choteau limestone. 



winchelli, see Crenipecten Winchelli. 

 AVICULOPINNA, Meek, 1867, Am. Jour. Sci., 

 vol. 44, 2d ser., p. 282. [Ety. the genera 

 Avicula and Pinna.] Compressed, slen- 

 der, elongated, subtrigonal, or nearly in 

 the form of a Pinna; beaks nearly ob- 

 solete, extremely oblique, and slightly 

 behind the anterior extremity. Type 

 A. americana. 



americana, Meek, 1867, Am. Jour. Sci., 

 vol. 44, 2d ser., p. 282, and Pal. E. Neb., 

 p. 197, Coal Meas. 



FIG. 785. Avlculopinua americana. 



illinoisensis, Worthen, 1884, Bull. No. 2, 



111. St. Mus. Nat. Hist., p. 13, and Geo. 



Sur. 111., vol. 8, p. 128, Coal Meas. 

 xinus, Sowerby, 1821, Min. Conch., vol. 3. 



[Ety. axine, battle-axe.] This genus is 



unknown in Palaeozoic rocks. 



ovatus, see Schizodus ovatus. 



securis, Shumard, 1859, Trans. St. Louis 

 Acad. Sci., Permian Gr. Not recognized. 

 BAKEVELLIA, King, 1849, Perm. Foss., p. 166. 

 [Ety. proper name.] Shell aviculiform, 

 subequivalve ; valves sinuous, gaping in 

 front for the passage of the byssus ; 

 um bones depressed, oblique; surface 

 with concentric striae; hinge with linear 

 anterior and posterior lateral teeth par- 

 allel to the cardinal margin ; muscular 

 scars as in Pteria ; cardinal area in both 

 valves ; two to five cartilage furrows in 

 each valve. Type B. antiqua. 



antiqua, Munster, 1826, (Avicula antiqua,) 

 Goldfuss Germ. Petref. Not American. 



illinoisensis, Worthen, 1884, Bull. No. 2, 

 111. St. Mus. Nat. Hist., p. 14, and Geo. 

 Sur. 111., vol. 8, p. 126, Up. Coal Meas. 



parva, Meek & Hayden, 1858, 

 Trans. Alb. Inst., vol. 4, p. 

 78, and Pal. Up. Mo., p. 57, 

 Permian Gr. PIQ 736 



(?) pulchra, Swallow, 1858, Bakevellia 

 Trans. St. Louis Acad. Sci., parva - 

 vol. 1, p. 189, Permian Gr. 



sulcata, Geinitz, 1866, (Gervillia sulcata,) 

 Garb, und Dyas in Neb., p. 33, Coal Meas. 

 BYSSOPTERIA, Hall, 1883, Pal. N. Y., vol. 5, 

 pt. 1, p. 4. [Ety. byssos, byssus; Pteria, 

 a genus.] Shell erect, equivalve, alate 

 posteriorly, truncate, with a nasute pro- 

 jection in front; surface radiately fur- 

 rowed and concentrically lined. Type 

 B. radiata. 



FIG. 787. Byssopterla radiata. 



radiata, Hall, 1883, Pal. N. Y., vol. 5, pt. 



1, p. 252, Up. Chemung Gr. 

 CARBONARCA, Meek & Worthen, 1870, Proc. 

 Acad. Nat. Sci. Phil., p. 39. [Ety. 



