GRY. ISO.] 



LAMELLIBRANCHIA TA. 



483 



chemungensis, Pitt, 1874, Bui. Buff. Soc. 



Nat. Hist., Chemung Gr. 

 circularis, Hall, 1870, Prelim. Notice Lam. 



Shells, p. 51, and Pal. N. Y., vol. 5, pi. 



57, figs. 3-6, Ham. and Chemung Grs. 

 communis, Hall, 1885, Pal. N. Y., vol. 5, 



p. 378, Chemung Gr. 

 cotistricta, Hall, 1870, Prelim. Notice Lam. 



Shells, p. 58, and Pal. N. Y., vol. 5, pi. 



59, figs. 13-20, Ham. Gr. 

 cuneata, Hall, 1883, Pal. N. Y., vol. 5, pi. 



62, figs. 1-9, Ham. Gr. 

 duplicata, Hall, 1885, Pal. N. Y., vol. 5, p. 



380, Chemung Gr. 

 elliptica, Hall, 1870, Prelim. Notice Lam. 



Shells, p. 53, and Pal. N. Y., vol. 5, pi. 



58, figs. 1-12, Chemung Gr. 



erecta, Hall, 1870, Prelim. Notice Lam. 

 Shells, p. 52, and Pal. N. Y., vol. 5, p. 

 363. Ham. Gr. 

 glabra, Hall, 1885, Pal. N. Y., vol. 5, p. 



369. Chemung Gr. 



globosa, Hall, 1870, Prelim. Notice Lam. 

 Shells, p. 57, and Pal. N. Y., vol. 5, p. 

 372, Ham. Gr. 

 hamUlonensis, syn. for G. bisculcata. 



hannibalensis, 

 Shumard, 

 1855, (Allo- 

 risma han- 

 n i b alense,) 

 Geo. 8 u r . 

 Mo., p. 206, 

 C h o t e a u 

 and Kinder- 

 hook Grs. 



lirata, Hall. 1870, Prelim. Notice Lam. 

 Shells, p. 57, and Pal. N. Y., vol. 5, pi. 



59, figs. 6-12, Ham. Gr. 



magna, Hall, 1870, Prelim. Notice Lam. 



Shells, p. 50, 



and Pal. N. Y., 



vol. 5, p. 362, 



Ham. Gr. 

 minor, Walcott, 



1885, Monogr. 



TJ. S. Geo. Sur., 



vol. 8, p. 174, Fig. 832. Grammysia ban- 

 Up. Devonian, nlbalensis. Bight side 

 nodocostata.Hall, view> 



1870, Prelim. Notice Lam.Shells,p.50,and 



Pal. N.Y.,vol.5,pl. 55, figs. 1-11, Ham. Gr. 

 obsoleta, Hall, 1870, Prelim. Notice Lam. 



Shells, p. 60, and Pal. N. Y., vol. 5, pi. 



59, figs. 21-27, Ham. Gr. 

 ovata, Hall, 1885, Pal. N. Y., vol. 5, p. 



358, Up. Held. Gr. 

 parallela, Hall, 1870, Prelim. Notice Lam. 



Shells, p. 59, Ham. Gr. 

 plena, Hall, 1885, Pal. N. Y., vol. 5, p. 



382, Waverly Gr. 

 prsecursor, Hall, 1870, Prelim. Notice Lam. 



Shells, p. 54, and Pal. N. Y., vol. 5, pi. 



59, fig. 1, Schoharie grit, 

 remota, Billings, 1874, Pal. Foss., vol. 2, 



p. 139, Up. Sil. 

 rhomboidalis, Meek & Worthen, 1865, 



Proc. Acad. Nat. Sci. Phil., p. 248, and 



Geo. Sur. 111., vol. 3, p. 439, Ham. Gr. 



FIG. 831. Grammysia hanni- 

 balensis. Dorsal view. 



rhomboides, Meek, 1871, Proc. Acad. Nat. 

 Sci. Phil., p. 72, and Ohio Pal., vol. 2, p. 

 302, Waverly Gr. 



rustica, Billings, 1874, Pal. Foss., vol. 2, 

 p. 139, Up. Sil. 



secunda, Hall, 1870, Prelim. Notice Lam. 

 Shells, p. 54, and Pal. N. Y., vol. 5, pi. 

 59, figs. 2-5, Up. Held. Gr. 



subarcuata, Hall, 1870, Prelim. Notice 

 Lam. Shells, p. 61, and Pal. N., vol. 5, 

 pi. 61, figs. 10-22, Chemung Gr. 



undata, Hall, 1883, Pal. N. Y., vol. 5, p. 

 379, Chemung Gr. 



ventricosa, Meek, 1871, Proc. Acad. Nat. 

 Sci. Phil., p. 73, and Ohio Pal., vol. 2, 

 p. 303, Waverly Gr. 

 Gryphorhynchus, Meek, 1864, Am. Jour. Sci. 



and Arts. Not. defined. 

 ILIONIA, Billings, 1875, Can. Nat. and Geol., 

 vol. 8, p. 301. [Ety. proper name.] Ir- 

 regularly ovate, compressed; one ex- 

 tremity larger than the other, with 

 beaks turned toward the larger end ; 

 concave depression from the umbones 

 to the posterior ventral margin ; sub- 

 ovate muscular impression in the upper 

 half of the posterior extremity. Type 



1. canadensis. 



canadensis, Billings, 1875, Can. Nat. and 

 Geol., vol. 8, p. 301, Corniferous Gr. 



costulata, Whit- 

 eaves, 1884, 

 Pal. Foss., vol. 

 3, p. 15,Guelph 

 Gr. 



galtensis, Whit- 

 eaves, 1884, 

 Pal. Foss., vol. 

 3, p.!5,Guelph 

 Gr. FIG- 833. Ilionia galtensis. 



sinuata, Hall, 



1859, (Anatina sinuata,) Pal. N. Y., vol. 

 3, p. 265, Low. Held. Gr. 

 Inoceramus, Sowerby, 1818, Min. Conch., vol. 



2. This genus is unknown in Ameri- 

 can Palaeozoic rocks. 



chemungensis, see Mytilarca chemungensis. 

 mytilimeris, see Plethomytilus mytiliraeris. 

 oviformis, see Plethomytilus oviformis. 

 ISCHYRINIA, Billings, 1866, Catal. Sil. Foss. 

 Antic., p. 16. [Ety. ischyros, strong.] 

 Equivalve, inequilateral ; two strong 

 ridges radiating from the beak in the 

 interior of each valve. Type I. win- 

 chelli. 



plicata, Bill- 

 ings, 1866, 

 Catal. Sil. 

 Foss. Antic., 

 p. 52, Anti- 

 costi Gr. 

 winchelli, Bil- 

 lings, 1866, 

 Catal. Sil. 

 Foss. Antic., 

 p. 16, Hud. 

 Riv. Gr. 



Isocardia, Klein, 1753, Tent. Meth. Ostr. 

 [Ety. isos, like ; kardia, the heart.] Thi& 



FIG. 834. Ischyrinia win- 

 chelli. 



