PLE.] 



GASTEROPODA. 



419 



Plbukonotus, Hall, 1879, Pal. N. Y., vol. 

 5, pt. 2, p. 138. [Ety. pleura, side ; 

 notos, back.] Distinguished from Euom- 

 phalus by the broadly expanded aper- 

 ture, sinuate on the upper margin, 

 making a deep retral angle, which 

 meets a peripheral band. Type P. 

 decewi. 



Fig. 699.— Pleuronotus decewi. 



decewi, Billings, 1861, (Euomphalus 

 decewi,) Can. Jour., p. 358, Up. 

 Held. Gr. 

 Pleurotomakia, Defrance, 1824, Tableau d. 

 Corps. Organises Fossiles, p. 114, and 

 Diet. Sci. Nat., t. 41, p. 381 . [Ety. pleura, 

 side; tome, cut or notch.] Shell trochi- 

 form, more or less conical, pearly within, 

 variable in thickness, with or without 

 an umbilicus; volutions angular, flat- 

 tened, or rounded ; 

 surface ornamented 

 with striae, nodes, 

 granulations, or car- 

 inse; aperture sub- 

 quadrate, semioval, 

 suborbicular, or sub- 

 rhombic ; inner lip 

 thin ; fissure of outer 

 lip narrow and Pig. 700.— Pleuroto- 

 deep; revolving maria anglica. 

 band corresponding 

 in depth with the sinus. Type P. an- 

 glica. 



abrupta, Billings, 1859, Can. Nat. and Geo., 

 vol. 4, p. 354, Calciferous Gr. 



acadica, Dawson, 1883, Rep. on Redpath 

 Mus., p. 11, Subcarboniferous. 



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

 St. Mus. Nat. Hist., p. 5, and Geo. Sur. 

 111., vol. 8, p. 137, Coal Meas. 



adjutor, Hall', 1879, Pal. N. Y., vol. 5, pt. 

 2, p. 80, Up. Held Gr. 



ad vena, Winchell, 1864, Am. Jour. Sci. 

 and Arts, 2d series, vol. 37, p. 228, Pots- 

 dam Gr. 



agarista, Billings, 1865, Pal. Foss., vol. 1, 

 p. 230, Quebec Gr. 



agave, Billings, 1865, Pal. Foss., vol. 1, p. 



170, Trenton Gr. 

 ambigua, Hall, 1847, Pal. N. Y., vol. 1, p. 



176, Trenton Gr. 

 americana, Billings, 1860, Can. Nat. and 



Geo., vol. 5, p. 164, Trenton Gr. 

 amphitrite, Billings, 1862, Pal. Foss., vol. 

 1, p. 32, Chazy or Black Kiv. Gr. 



angulata, Conrad, 1843, Proc. Acad. 

 Nat. Sci. Phil. This name was 

 preoccupied by Sowerby. 

 antiquata, Hall, 1847, Pal. N. Y., vol. 



1, p. 31, Chazy Gr. 

 aperia, see Raphistoma apertum. 

 apicalis, Hall, 1876, Illust. Devonian 

 Foss., pi. 20, and Pal. N. Y., vol. 

 5, pt. 2, p. 88, Chemung Gr. 

 arabella, Billings, 1865, Pal. Foss., 



vol. 1, p. 343, Calciferous Gr. 

 arachne, Billings, 1862, Pal. Foss., 



vol. 1. p. 31, Black Riv. Gr. 

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

 Mus. Nat. Hist., p. 42, and Pal. 

 N. Y., vol. 5, pt. 2, p. 64, Scho- 

 harie grit, 

 arata var. clausa, Hall, 1879, Pal. 

 N. Y., vol. 5, pt. 2, p. 65, Up. 

 Held. Gr. 

 axion, Hall, 1867, 20th Rep. N. Y. 

 Mus. Nat. Hist., p. 394, Niag- 

 ara Gr. 

 beckwithana, McChesney, 1860, Desc. 



New Pal. Foss., p. 61, Coal Meas. 

 beekmanensis, Whitfield, 1889, Bull. Am. 

 Mus. Nat. Hist., vol. 2, p. 53, Calcifer- 

 ous Gr. 

 biangulata, Hall, 1847, Pal. N. Y., vol. 1, 



p. 31, Chazv Gr. 

 bicarinata, McChesney, 1860. Preoccu- 

 pied. See P. turbiniformis. 

 bilix, see Cyclonema bilix. 

 bispiralis, Hall, 1852, Pal. N. Y., vol. 2, 



p. 348, Guelph Gr. 

 bonharborensis, Cox, 1857, Geo. Sur. Ky., 



vol. 3, p. 567, Coal Meas. 

 brazoensis, Shumard, 1860, Trans. St. 

 Louis Acad. Sci., vol. 1, p. 624, and 

 Geo. Sur. 111., vol. 2, p. 354, Low. Coal 



Moaa 



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



Geo. Sur. Terr., p. 169, Coal Meas. 

 calcifera, Billings, 1859, Can. Nat. and 



Geo., vol. 4, p. 352, Calciferous Gr. 

 calphurnia, Billings, 1865, Pal. Foss., vol. 



1, p. 230, Up. Taconic, Quebec Gr. 

 calyx, Billings, 1859, Can. Nat. and Geo., 



vol. 4, p. 454, Chazy Gr. 

 canadensis, Billings, 1865, Pal. Foss , vol. 



1, p. 342, Calciferous Gr. 

 capillaria, Conrad, 1842, Jour. Acad. Nat. 



Sci., vol. 8, p. 271, and Pal. N. Y., vol. 



5, pt. 2, p. 77, Ham. Gr. 

 carbonaria, Norwood & Pratten, 1854, 



Jour. Acad. Nat. Sci., 2d series, vol. 3, 



p. 75, Coal Meas. 

 casii, Meek & Worthen, 1868, Geo. Sur. 



111., vol. 3, p. 359, Niagara Gr. 

 cavumbilicata, Winchell, 1866, Rep. Low. 



Penin. Mich., p. 96, Ham. Gr. 



