SYNONYMIC EEFERENCES. 43 



Present reference. 



descendens [Acrotreta ophirensis], Walcott [1908d, p. 95]. Acrotreta optirensis descendens. 



desiderata [Billingsia], Ford [1886a, pp. 466 and 467] Elkania desiderata. 



desiderata [Elkania], Ford [1886b, p. 325] Do. 



Hall and Clarke [1892a, PI. Ill, figs. 13 and 14] Do. 



Hall and Clarke [1892c, pp. 76 and 77] Do. 



desiderata [Obolella], Billings [1862d, pp. 69-70] Do. 



Davidson [1868, p. 309] Do. 



desiderata [Obolella?], Walcott [1886b, p. Ill] Do. 



desideratus [Obolus (Lingulella)], Walcott [1898b, pp. 399-400] Lingulella desiderata. 



Walcott [1899, pp. 445-446, PI. LX, 



fig. 2] Do. 



Walcott [1899, pp. 445^46, PL LX, 



fig. 2a] Obolus rotundatus. 



desmopleura [Orthis], Meek [1S72, p. 295] Eoorthis desmopleura. 



desmopleura [Orthis (Plectorthis)], Walcott [1905a, p. 261] Do. 



desmopleura nympha [Orthis (Plectorthis)], Walcott [1905a, p. 262] Eoorthis desmopleura nympha. 



desquamata [Avicula?], Hall [1847, p. 292] Obolella crassa. 



desquamata [Obolella], Billings [1872a, p. 218] Do. ■ 



Billings [1872c, p. 356] Do. 



diablo [Orthis (Plectorthis)], Walcott [1905a, p. 262] Eoorthis? diablo. 



dice [Billingsella], Walcott [1905a, p. 234] Billingsella dice. 



Dicellomus Grabau and Shimer [1907, p. 189] Dicellomus. 



Hall [1873, p. 246] Do. 



Hall and Clarke [1892a, pp. 240-241] Do. 



Hall and Clarke [1892c, pp. 66-73] Do. 



Walcott [1899, p. 446] Do. 



Walcott [1905a, pp. 312-313] Do. 



Wal ;ott [1908e, PI. XI, and pp. 142 and 144] Do. 



Dicellomus appalachia Walcott [1905a, p. 314] Dicellomus appalachia. 



Dicellomus crassa Hall [1873, p. 246] Obolella crassa. 



Dicellomus nanus Walcott [1899, p. 447] Lingulella desiderata (in part) and Dicello- 

 mus nanus (in part). 



Walcott [1905a, pp. 314-315] Dicellomus nanus. 



Dicellomus parvus Walcott [1905a, pp. 315-316] Dicellomus parvus. 



Dicellomus pectenoides Walcott [1901, p. 673] Dicellomus pectenoides. 



Walcott [1905a, p. 316] Do. 



Dicellomus polita Hall [1873, p. 246] Dicellomus politus. 



Dicellomus politus Grabau and Shimer [1907, pp. 189-190] Do. 



Walcott [1899, pp. 443 and 446] Do. 



Walcott [1905a, pp. 313 and 316-818] Do. 



Dicellomus prolificus Walcott [1908d, p. 77] Dicellomus prolificus. 



Dicellomus sp. undt. Walcott [1905a, p. ,,319] Dicellomus sp. undt. 



dichotoma [Acrothele?], Walcott [1884b, pp. 14-15] Acrothele dichotoma. 



dichotoma [Acrotreta], Hall and Clarke [1892c, pp. 100 and 103] Do. 



Walcott [1886b, p. 107] Do. 



Discina buchii Eichwald [1860, p. 914] Helmersenia ladogensis (in part) and Key- 



serlingia buchi (in part). 



Discina contraria Barrande [1868a, p. 104] Orbiculoidea contraria. 



Barrande [1868b, pp. 692-693] Do. 



Pompeckj [1896a, p. 4] Do. 



Discina labiosa Salter [1866a, p. 285] Acrotreta sagittalia. 



Discina microscopica Shumard [1861, p. 221] Acrotreta microscopica. 



Discina pileolus Davidson [1868, pp. 312-313] Orbiculoidea pileolus. 



Davidson [1871, p. 344] Do. 



(Hicks MS.) Salter [1866a, p. 285] Do. 



Discina pileolus? Hicks [1871, PI. XY, figs. 12 and 12a] Stenotheca pileolus, a gastropod. 



Discina varians Barrande [1868a, pp. 103-104] Orbiculoidea varians. 



Barrande [1868b, p. 692] Do. 



Pompeckj [1896a, p. 4] Do. 



Discina sp. Miquel [1893, p. 9] Acrothele bergeroni. 



Miquel [1894a, p. 106] Do. 



Miquel [1894b, p. 10] Do. 



Miquel [1895, p. 10] Do. 



