PLA.] 



GASTEROPODA. 



417 



perplicatuin, Hall, 1859, Pal. N. Y., vol. 3, 



p. 325, Low. Held. Gr. 

 pileiforme, Hall, 1859, Pal. N. Y., vol. 3, 



p. 327, Low. Held. Gr. 

 piso, Walcott, 1885, Monogr. U. S. Geo. 



Sur., vol. 8, p. 254, Subcarboniferous. 

 platystoma, Hall, 1859, Pal. N. Y., vol. 3, 



p. 326, Low. Held. Gr. 

 platystoma var. alveatum, Hall, 1859, Pal. 



N. Y., vol. 3, p. 326, Low. Held. Gr. 

 plicatile, Hall, 1859, Pal. N. Y., vol. 3, p. 



325, Low. Held. Gr. 

 plicatum, Conrad, 1840, (Calceola plicata,) 

 Ann. Rep. N. Y., p. 207, and Pal. N. Y., 

 vol. 3, p. 334, Low. Held. Gr. 

 pritmevum, Billings, 1871, Can. Nat. and 



Geol., vol. 6, p. 220, Georgia Gr. 

 primordiale, Hall, 1863, 16th Rep. N. Y. 



Mus. Nat. Hist., p. 136, Potsdam Gr. 

 proclive, Ringueberg, 1886, Bull. Buf. Soc. 



Nat. Sci., vol. 5, p. 14, Niagara Gr. 

 pyramidatum, Hall, 1859, Pal. N. Y., vol. 



3, p. 336, Low. Held. Gr. 

 quincyense, McChesney, 1861, New Pal. 

 Foss., p. 90, and Geo. Sur. 111., vol. 3, 

 p. 510, Burlington Gr. 

 quinquesinuatum, Ulrich, 1886, Cont. to 



Am. Pal., p. 29, Up. Held. Gr. 

 reflexum, Hall, 1859, Pal. N. Y., vol. 3, p. 



477, Oriskany sandstone, 

 retrorsum, Hall, 1859, Pal. N. Y., vol. 3, 



p. 320, Low. Held. Gr. 

 retrorsum var. abnorme, Hall, 1859, Pal. 

 N. Y., vol. 3, p. 321, Low. Held. Gr. 



reversum, Hall, 

 1860, Supp. to 

 Geo. Rep. Iowa, 

 vol. 1, pt. 2, p. 

 91, Burlington 

 Gr. 

 rictum, Hall, 1862, 

 15th Rep. N. Y. 

 Mus. Nat. Hist., 

 p. 35, and Pal. 

 N. Y., vol. 5, pt. 

 2, p. 13, Ham. 

 and Up. Held. 

 Grs. 



robustum, Hall, 

 1859, Pal. N. Y., vol. 3, p. 313, Low. 

 Held. Gr. 

 senex, Winchell & Marcy, 1865, (Porcel- 

 lia senex,) Mem. Bost. Soc. Nat. Hist., 

 p. Ill, Niagara Gr. 

 serratum, Ulrich, 1886, Cont. to Am. Pal., 



p. 30, Up. Held. Gr. 

 sinuatum, Hall, 1859, Pal. N. Y., vol. 3, 



p. 314, Low. Held. Gr. 

 spinigerum, Worthen, 1873, Geo. Sur. 111., 



vol. 5, p. 594. Coal Meas. 

 spirale, Hall, 1859, Pal. N. Y., vol. 3, p. 



331, Low. Held.-Gr. 

 squalodens, Whitfield, 1882, Ann. N. Y. 

 Acad. Sci., vol. 2, p. 202, Up. Held. Gr. 

 subnodosum, Hall, 1859, Pal. N. Y., vol. 



3, p. 474, Oriskany sandstone, 

 subplicatum, Meek & Worthen, 1866, Proc. 

 Acad. Nat. Sci. Phil., p. 265, and Geo. 

 Sur. 111., vol. 3, p. 457, Kinderhook Gr. 



Fig. 695.— Platyceras re- 

 versum. 



subrectum, Hall, 1859, 12th Rep. N. Y., 

 Mus. Nat. Hist,, p. 18, and Pal. N. Y., 

 vol. 5, pt. 2, p. 1, Up. Held. Gr. 



subrectum, Hall, 1860, Supp. to Iowa Rep. 

 The name being preoccupied, Meek & 

 Worthen proposed P. infundibulum. 



subsinuosum, Worthen, 1882, Bull. No. 1, 

 111. St. Mus. Nat. Hist., p. 38, Low. 

 Held. Gr. Proposed instead of P. sub- 

 undatum, M. & W., which was preoc- 

 cupied. 



subundatum, Conrad, 1841, Ann. Rep. 

 N. Y., p. 56, Up. Held. Gr. 



subundatum, Meek & Worthen, 1868, Geo. 

 Sur. 111., vol. 3, p. 457. The name was 

 preoccupied. See P. subsinuosum. 



sulcatum, Conrad, 1841, Ann. Rep. N. Y., 

 p. 56, Oriskany sandstone. 



sulcoplicatum, Hall, 1859, Pal. N. Y., vol. 

 3, p. 324, Low. Held. Gr. 



svmmetricum, Hall, 1862,15th Rep. N.Y. 

 Mus. Nat. Hist, p. 34, and Pal. N. Y., 

 vol. 5, pt. 2, p. 9, Ham. and Up. 

 Held. Grs. 



tenuiliratum, Hall, 1859, Pal. N. Y., vol. 

 3, p. 317, Low. Held. Gr. 



thetiforme, Walcott, 1885, Monogr. U. S. 

 Geo. Sur., vol. 8, p. 184, Devonian. 



thetis, Hall, 1862, 15th Rep. N. Y. Mus. 

 Nat. Hist., p. 32, and Pal. N. Y., vol. 5, 

 pt. 2, p. 8, Up. Held, and Ham. Grs. 



thetis var. subspinosum, Hall, 1876, 

 Illust. Devonian Foss., pi. 3, Ham. Gr. 



tortum, Meek, 1871, Proc. Acad. Nat. Sci., 

 p. 171, and Ohio Pal., vol. 2, p. 345, 

 Coal Meas. 



tortuosum, Hall, 1859, Pal. N. Y., vol. 3, 

 p. 472, Oriskanv sandstone. 



tribulosum, White, 1880, 12th Rep. U. S. 

 Geo. Sur. Terr., p. 168, Burling- 

 ton Gr. 



trigonale, Stevens, 1858, (Acroculia tri- 

 gonalis,) Am. Jour. Sci. and Arts, vol. 

 25, p. 260, Carboniferous. 



trilobatum, Hall, 1859, Pal. N. Y., vol. 3, 

 p. 316, Low. Held. Gr. 



tubiforme, Hall, 1859, Pal. N. Y., vol. 3, 

 p. 332, Low. Held. Gr. 



uncum, Meek & Worthen, 1866, Proc. 

 Acad. Nat. Sci., p. 264, and Geo. Sur. 

 111., vol. 5, p. 516, Keokuk Gr. 



undatum, Hall, 1876, Illust. Devonian 

 Foss., pi. 7, and Pal. N. Y., vol. 5, pt. 



2, p. 17, Up. Held. Gr. 

 undulatum, Walcott, 1885, Monogr. U. S. 



Geo. Sur., vol. 8, p. 184, Devonian, 

 undulostriatum, Hall, 1859, Pal. N. Y., 



vol. 3, p. 336, Low. Held. Gr. 

 unguiforme, Hall, 1859, Pal. N. Y., vol. 3, 



p. 322, Low. Held. Gr. 

 uniseriale, Nicholson, 1874, Rep. Pal. 



Ont, p. 116, Up. Held. Gr. 

 unisulcatum, Hall, 1859, Pal. N. Y., vol. 



3, p. 316, Low. Held. Gr. 

 ventricosum, Conrad, 1840, Ann. Rep. 



N. Y., p. 206, and Pal. N. Y., vol. 3, p. 

 311, Low. Held. Gr. 

 vomerium, Winchell, 1863, Proc. Acad. 

 Nat. Sci., p. 19, Marshall Gr. 



