982 BULLETIN 92, UNITED STATES NATIONAL MUSEUM. 



PIZARROA Hoek. Genotype: P. quickuana Hoek. 



Pizarroa Hoek, Neues Jahrb. Min. Geol. Pal., 34. 1912, p. 246. 



Pizarroa quickuana Hoek. 



Pizarroa quickuana Hoek, Neues Jahrb. Min. Geol. Pal., 34, 1912, p. 246, pi. 8, 



figs. 14, 15. 

 Ordovician: Totorapampa, Bolivia. 



PLACENTULA Jones and Holl. Genotype: Primitia excavata Jones and Holl. 



Placentula Jones and Holl, Ann. Mag. Nat. Hist., 5th ser., 17, 1886, p. 407. 

 Miller, N. A. Geol. Pal., 1st App., 1892, p. 710. Grabau and Shimer, N. A. 

 Index Fossils, 2, 1910, p. 351. 



Placentula inornata Ulrich. 



Placentula inornata Ulrich, Jour. Cincinnati Soc. Nat. Hist., 13, 1890, p. 124, pi. 



10, figs. 14a, b. 

 Eden (Economy): Covington, Kentucky. 



Placentula marginata Ulrich. 



Placentula marginata Ulrich, Jour. Cincinnati Soc. Nat. Hist., 13, 1890, p. 124, 



pi. 10, figs. 13a-c. Grabau and Shimer, N. A. Index Fossils, 2, 1910, p. 351, 



figs. 1666d, d'. 



Maysville (Corryville) : Cincinnati, Ohio. 

 Holotype.C&t. No. 41364, U.S.N.M. 



PLACOCYSTTS BALANOIDES Haeckel. See Ateleocystites balanoides. 

 PLACOCYSTIS CRUSTACEA Haeckel. See Ateleocystites balanoides. 

 PL^ESIOMYS Hall and Clarke. See Dinorthis Hall and Clarke. 

 PUESIOMYS LORICULA Hall and Clarke. See Dinorthis (Plsesiomys) deflecta. 



PL^SIOMYS PORCATA Hall and Clarke. See Dinorthis (Plsesiomys) porcata anticos- 

 tiensis. 



PL^SIOMYS RECTA Hall and Clarke. See Dinorthis (Plsesiomys) deflecta. 

 PI^ESIOMYS RETRORSA Hall and Clarke. See Dinorthis carleyi. 



PLANOLITES Nicholson. Genotype: P. vulgaris Nicholson. 



Planolites Nicholson, Proc. Roy. Soc. London, 21, 1873, p. 289. Nicholson and 



Hinde, Canadian Jour., n. s., 14, 1874, p. 138. Nicholson, Rep. Pal. Prov. 



Ontario, pt. 2, 1875, p. 41. Miller, N. A. Geol. Pal., 1889, p. 520. Walcott, 



Proc. U. S. Nat. Mus., 12, 1890, p. 34. 



PLANOLITES VIRGATUS Walcott. See Palaeophycus virgatum. 



Planolites vulgaris Nicholson. 



Planolites vulgaris Nicholson and Hinde, Canadian Jour., n. s., 14, 1874, p. 139. 



Nicholson, Rep. Pal. Prov. Ontario, pt. 2, 1875, p. 42. 

 Upper Medinan (Cataract): Dundas, Ontario. 



PLANORBIS TRILOBATUS Conrad. See Bucanella trilobata. 



PLASMOPORA Edwards and Haime. Genotype: Porites petal iformis Lonsdale. 

 Plasmopora Edwards and Haime, Compt. Rend, de 1'Acad. Sci., 29, 1849, p. 262; 

 Mon. d. Polyp. FOBS. d. Terr. Pal., 1851 (Arch du Mus. d'Hist. Nat., 5), pp. 

 150, 221. Pictet, Traite de Pal., 2d ed., 4, 1857, p. 438. Milne-Edwards, 

 Hist. Nat. d. Corall., 3, 1860, p. 239. Rominger, Geol. Surv. Michigan, 3, 

 pt. 2, 1876, p. 13. Nicholson, Tab. Corals Pal. Period, 1879, p. 245. Zittel, 



