48 BULLETIN 100, UNITED STATES NATIONAL MUSEUM 



Notoplites Harmer, 1923. Family Scrupocellariidae. 



Ochetosella Canu and Bassler, 1917. Family Stomachetosellidae. 



Odontionella Canu and Bassler, 1917. Family Aspidostomatidae. 



Ogiva Jullien, 1881. Family Opesiulidae. Genotype Eschara actea D'Orbigny, 

 1851. Cretaceous. An inexact Cretaceous genus. 



Ogivalia Jullien, 1881. Family Opesiulidae. Cretaceous. Genotypes, Vincu- 

 laria elegans D'Orbigny, 1851 and Eschara santonensis D'Orbigny, 1851. 

 An inexact genus. 



Ogivalina Canu and Bassler, 1917. Family Hincksinidae. 



Oligotopora Lang, 1916. Family Andrioporidae. Cretaceous cribrimorph. 



Oligotresium Gabb and Horn, 1862. Synonym of Lunularia. 



Omalosecosa Canu and Bassler, 1925. Family Celleporidae. 



Omoiosia Canu and Bassler, 1927. Family Membranicellariidae. 



Onchopora Busk, 1855. Family Onchoporidae. 



Onchoporella Busk, 1884. Family Onchoporidae. 



Onchoporoides Ortmann, 1890. Family Onchoporidae. 



Onychocella Jullien, 1881. Family Opesiulidae. 



Oochilina Norman, 1903. Synonym of Crassimarginatella. 



Opislhornithopora Lang, 1916. Family Pelmatoporidae. Cretaceous cribri- 

 morph. 



Qrbitulipora Stoliczka, 1861. Family Orbituliporidae. 



Omatella Canu, 1900. Genotype Membranipora ornata D'Orbign>, 1850. Cre- 

 taceous. Incompletely studied. 



Omithopora D'Orbigny,. 1852. Synonym of Bugula. 



Ornilhoporina D'Orbigm , 1852. Synonym of Bugula. 



Orthopora Waters, 1904. See Orthoporidra. 



Orthoporidra Canu and Bassler ; 1927. Proposed for Orthopora Waters, 1904 (not 

 Hall, 1886). Family Lekythoporidae. 



Osthimosia Jullien, 1888. Family Celleporidae. 



Otionella Canu and Bassler, 1917. Family Bifiustridae. 



Otopora Lang, 1916. Family Otoporidae. Cretaceous cribrimorph. 



Ovaticella Maplestone, 1900. Type 0. turbinata Maplestone, 1900. Tertiary of 

 Australia. Type incomplete Synonym or close to Adeonellopsis. 



Pachydera Marsson, 1887. Pal. Abb., vol. 4, p. 100. Type and only species, 

 P. grandis Marsson. Costulae. Referred by Lang to Pelmatoporidae. 



Pachykraspedon Koschinsky, 1885. First species, P. clarum Koschinsky, 1885. 

 Palaeontographica, vol. 32, 1885, p. 43. ?Synonym for Mastigophora. 



Pachystomaria MacGillivray, 1895. Family Galeopsidae. 



Pachytheca Canu, 1913. Family Acroporidae. 



Palmicellaria Alder, 1864. Family Smittinidae. 



Pancheilopora Lang, 1916. Family Andrioporidae. Cretaceous cribrimorph. 



Parmularia Maplestone, 1910. Family Parmulariidae. 



Pasylhea Lamouroux, 1812. Family Liriozoidae. 



Pavolunulites D'Orbigny, 1852. Bry. Cret., p. 358. Only a growth form of 

 Lunularia. 



Pelmatopora Lang, 1916. Family Pelmatoporidae. Cretaceous cribrimorph. 



Peneclausa Jullien, 1888. Synonym of Micropora. 



Pergensina Jullien, 1888. Synonym of Thairopora. 



Perigastrella Canu and Bassler, 1917. Family Phylactellidae. 



Periporosella Canu and Bassler, 1917. Family Alderinidae. 



Peristomella Levinsen, 1902. Family Escharellidae. 



Periteichisma Koschinsky, 1885. Palaeontographica, vol. 32, p. 25. First 

 species, Vincularia geometrica Reuss, 1869. Second species, Cellepora de- 

 planata Reuss, 1847. Fossils incompletely studied. 



