scHucHKRT] INDEX AND BIBLIOGRAPHY. 285 



Oitbis cyclas Hall=Ehipidomel]a cyclas. 



Ortbis cyclus Jauies=Dalmanella testudinaria emacerata. 



Orthis cypha Jaines=Platystroi)liia laticosta. 



Orthis dalyana Miller =Rliipidomella dalyana. 



Orthis davidsoni deYerneuil. Anticosti and Niagara (Sil.). 



Orthis davidsoni de Verneuil, Bull. Soc. Gt5ol. de France, 2d ser., V, 1848, l^. 341, 

 pi. 4, fig. 9.— Billings, Geol. Canada, 1S63, p. 312, tig. 318.— Hall and Clarke, 

 Pal. New York, VIII, Pt. 1, 1892, pp. 192, 193, 221, 228, pi. 5, figs. 5-8. 



Ortliis alata Staler, Bull. Mus. Conip. Zool., 4, 1865, p. 66. 



Orthis calligramma var. davidsoni Nicholson and Hinde, Canadian Jour., n. ser., 

 XIV, 1874, p. 144.— Nicholson, Pal. Prov. Ontario, 1875, p. 47, fig. 21g. 



Loc. Europe; Anticosti; Dundas, Ontario. 



Orthis daytonensis Foerste=Hebertella daytonensis. 

 Orthis deformis Hall=Orthothetes deformis. 



Ortliis (?) delicatula Billiugs. ! Calciferous (Ord.). 



Orthis delicatula Billings, Pal. Fossils, I, 1865, p. 217. 

 Loc. Pistolet Bay and near Portland Creek, Newfoundland. 



Orthis dentata Meek (non Pander) =Platystrophia crassa. 



Orthis (?) desmopleura Meek. Calciferous (Ord.). 



Orthis coloradoensis Meek (non Shumard), Proc. American Phil. Soc, II, 1870, 



p. 425. 

 Orthis desmopleura Meek, Hayden's U. S. Geol. Survey Wyoming, 1872, p. 295. 

 Loc. Colorado City and Manitou, Colorado. 



Orthis dichotonia Hall=Plectorthis dichotoma. 

 Orthis discus nall=Rhipidomella discus. 

 Orthis disparilis Conrad = Orthis triceuaria. 

 Orthis disparilis Owen=Dalmanella testudinaria. 



Orthis disparilis Kay ser. Ordovician. 



Orthis disparilis Kaj^ser (non Conrad), Palicontographica, Suppl., Ill, 1876, p. 



26, pi. 3, figs. 4-8. 

 Loc. Potrero de los Angulos, etc., Argentine Republic. 

 Oia. Probably a new species. 



Orthis dubia Hall=Rhipidomella dubia. 



Orthis eboracensis Miller=Dalmanella lenticularis. 



Orthis electra Billings=Dalmanella electra. 



Orthis elegantula Dalnian=Dalmanella elegantula. 



Orthis elegantula parva Foerste=Dalnianella elegantula parva. 



Orthis ella Hall=Plectorthis ella. 



Orthis emacerata Hall=Dalmanella testudinaria emacerata. 



Orthis emacerata Meek (non Hall)=Dalinanella testudinaria meeki. 



Orthis emarginata Hall = Rhipidomella oblata emarginata. 



Orthis eminens Hall = Rhii3idomella eminens. 



Orthis erratica Hall = Catazyga erratica. 



Orthis (?) eryna Hall. Oorniferous (Dev.). 



Orthis iBquivalvis Hall (non Hall, 1847), Tenth Rep. New York State Cab. Nat. 



Hist., 1857, p. 109. 

 Orthis eryna Hall, Sixteenth Rep. Ibidem, 1863, p. 35 ;— Pal. New York, IV, 1867, 



corrigenda. 

 Orthis Idas Hall, Pal. New York, IV, 1867, p, 42, pi. 5, fig. 11. 

 Loc. Williamsville, New York. 

 Obs. Possibly a species of Hipparionyx. 



