888 BULLETIN 92, UNITED STATES NATIONAL MUSEUM. 



Orthis calligramma var. davidsoni Nicholson and Hinde. See Orthis davidsoni. 

 Orthis calligramma var. dinorthis Foerste. See Orthis flabellites dinorthis. 

 Orthis calligramma var. euorthis Foerste. See Orthis flabellites euorthis. 



Orthis (Dinorthis) calligramma var. itssiplicata Foerste. See Orthis flabellites 

 fissiplicata. 



Orthis canalis Hall. See Dalmanella elegantula. 



Orthis carausii Salter. 



Orthis carausii (Salter, MS.) Davidson, Geol. Mag. London, 5, 1868, p. 315, pi. 16, 



fig. 23.— Hoek, Neues Jahrb. Min. Geol., Pal., 34, 1912, p. 222. 

 Orthis carausii? Matthew, Trans. Royal Soc. Canada, 10, 1893, p. 102, pi. 7, fig. 7. 

 Lowest Ordovician: England; near St. John, New Brunswick (Bretonian — Div. 



3a); Bolivia. 



Orthis carleyi Hall. See Dinorthis carleyi. 



Orthis centrilineata Hall. See Dalmanella centrilineata. 



Orthis centrosa Miller. See Platystrophia crassa. 



Orthis charlotte Winchell. See Dinorthis pectinella. 



Orthis circularis Winchell. See Pianoderua subasquata circularis. 



Orthis circularis Owen. See Rhipidomella circularis. 



Orthis circulus Hall. See Rhipidomella circulus. 



Orthis cincinnatiensis Miller. See Orthis(?) pumila. 



Orthis clytie Hall. See Heterorthis clytie. 



Orthis coloradoensis Shumard. See Billingsella coloradoensis. 



Orthis coloradoensis Meek. See Eoorthis desmopleura. 



Orthis concinna Hall. See Dalmanella concinna. 



Orthis conradi Winchell. See Pianodema subaequata conradi. 



Orthis corinna Billings. 



Orthis corinna Billings, Pal. Fossils, 1, Geol. Surv. Canada, 1865, p. 302, fig. 292. 

 Orthis? corinna Hall and Clarke, Pal. New York, 8, pt. 1, 1892, p. 217. 

 Canadian (Beekmantown) : Stanbridge, Quebec. 



Orthis corpulenta Sardeson. See Dalmanella corpidenta. 



Orthis costalis Hall. 



Orthis costalis Hall, Pal. New York, 1, 1847, p. 20, pi. 4, fig. 4a (not 4b-4c); 2d 



Ann. Rep. New York State Geol., 1883, pi. 34, fig. 35.— Hall and Clarke, Pal. 



New York, 8, pt. 1, 1892, pp. 221, 228, pi. 5, figs. 16-17.— Lesley, Geol. Surv. 



Pennsylvania, Rep. P4, 1889, p. 512, figs. — Grabau and Shimer, N. A. Index 



Fossils, 1, 1907, p. 250, fig. 300a-b.— Raymond, Ann. Carnegie Mus., 7, 1911, 



p. 235, pi. 35, fig. 4. 

 Middle Chazy or Black River: Chazy, New York. 



Orthis costata Hall. See Orthis(?) pumila. 



Orthis costata Miller. See Platystrophia crassa. 



