BIBLIOGEAPHIC LIST OF GENERA AND SPECIES. 1023 



Polytropis Dekoninck. See Poleumite Clarke and Ruedemann. 



PONTOBDELLOPSIS Ruedemann. Genotype: P. cometa Ruedemann. 



Pontobdellopsis Ruedemann, Bull. New York Slate Mus., 42, 1901, p. 574. 



Pontobdellopsis cometa Ruedemann. 



Pontobdellopsis cometa Ruedemann, Bull. New York State Mus., 42, 1901, 



p. 574, pi. 1, figs. 14-18. 

 Trenton (Snake Hill): Rural Cemetery, near Albany, New York. 



PONTOCYPRIS Sara. Genotype: P. serrulata Sars. 



Pontocypris Sara, Overaigt af Norges Marine Ostracoder, 1865, p. 15. — Brady, 

 Intellectual Observer, 12, London, 18G7, p. 118. — Ulrich, Zittel-Eaatman 

 Textb. Pal., 1, 1900, p. 646.— Bassler, ibid., 2d ed., 1913, p. 740. 



Pontocypris arcuata Ulrieb and Bassler. 



Pontocypris arcuata Ulricb and Bassler, Maryland Geol. Surv., Low. Dev., 1913, 



p. 541, pi. 98, figs. 23-25. 

 Helderbergian (Keyser): Cumberland, Maryland. 

 Eolotypc.—Q&t. No. 53288, U.S.N.M. 



Pontocypris(?) illinoisensis Ulricb. 



Pontocypris(?) illinoisensis Ulrich, Jour. Cincinnati Soc. Nat. Hist., 13, 1890, 



p. 107, pi. 10, figs. 16a-c. 

 Richmond (Maquoketa) : Savannah, Illinois. 

 Eolotype — Cat. No. 41333, U.S.N.M. 



Pontocypris niawi breviata Jones. 



Pontocypris mawii var. breviata Jones, Ann. Mag. Nat. Hist., 6th ser., 4, p. 269, 



pi. 15, fig. 4. — Ulrich and Bassler, Maryland Geol. Surv., Low. Dev., 1913, 



p. 541, pi. 98, figs. 26-28. 

 Silurian: Gotland. 



Helderbergian (Keyser): Cumberland, Maryland. 

 Coty pes. —Cat. No. 53287, U.S.N.M. 



Porambonites obscurus Hall and Whitfield. See Parastrophia(?) obscura. 



Porambonites? ottawaensis BilLings. See Rhynchotrema ottawaense. 



Porcellia (part) of authors. See Oxydiscus Koken. 



Porcellia ornata Sharpe. See Cyrtolites ornatus. 



Porcellia senex Winchell and Marcy. See Platyceras senex. 



Porites? astraformis Owen. See Plasmopora follis. 



Porites inordinata Lonsdale. See Heliolites inordinata. 



Porites megastoma McCoy. See Heliolites megastoma. 



Porites petalliformis Lonsdale. See Plasmopora petaliformis. 



Porites? vetusta Hall. See Protaraea vetusta. 



POROCRINUS Billings. Genotype: P. conicus Billings. 



Porocrinus Billings, Geol. Surv. Canada, Rep. Progr. for 1853-56, 1857, p. 279; 

 Geol. Surv. Canada, dec. 4, 1859, p. 33, fig. 13.— Meek and Worthen, Proc. 

 Acad. Nat. Sci. Philadelphia, 1865, p. 145; Geol. Surv. Illinois, 3, 1868, 

 p. 329.— Zittel, Handb. Pal., 1, Munich, 1879, p. 420.— Grant, Trans. Ottawa 

 Field Nat. Club, 1, 1881, p. 42.— Miller, N. A. Geol. Pal., 1889, p. 273; Zittel- 



