CATALOGUE OF TRILOBITES. 259 



A CATALOGUE OF NORTH AMERICAN SPECIES OF TRILOBITES. 



Acanlholoma Con., 1840; 3d Ann. Rep. Pal. Dept. New York Geol. Survey, 

 p. 205. (See Acidaspis tuber culatus.) 



apinosa Con. (See Acidaspis tuber culatus.) 



ACIDASPIS Murch., Silurian System, 1839, p. 658. Cambrian and Silurian. 

 Used as a subgroup by Clarke. Notes on the genus Acidaspis, 1892, 

 p. 9; for species with a single large straight median spine on the 

 occipital ring, Acidaspis brightii Murch. 



Ceratocephala Ward., 1838; Am. Jour. Sei., 1st series, vol. 34, p. 377. 

 Used in the generic sense by Clarke. Notes on the genus Aci- 

 daspis, 1892, p. 9; for species with two straight divergent spines 

 on the occipital ring, Ceratocephala goniata Ward. 

 Odontopleura Emm., 1839; De Tril., p. 53. 



Used as a subgeuus by Clarke. Notes on the genus Acidaspis, 

 1892, p. 9; for species having the occipital ring smooth or with 

 central tubercle, Odontopleura ovata Emm. 



Arges Goldf. (in part), Neues Jahrb. fiir Mineral, 1843, pp. 544, 556. 

 Ceraurus (Green) Loven, 1845, Kong. Svenska Vet. Akad., p. 46. 

 Polyeris Rouault, 1846; Bull. Soc. Geol. France, vol. 4, p. 320. 

 Selenopeltis Cord, 1847; Prodr., p. 34. 



Used as a subgenus by Clarke. Notes on the genus Acidaspis, 1892, 

 p. 9; for species with confluent glabella lobes, oblique thoracic, 

 pleural and spineless pygidium, Selenopeltis buchi Barr. 

 Trapelocera Cord., 1847; Prodr., p. 158. 

 Dtcranurus Con., 1841; 5th Ann. Rep. Pal. Dept. New York Geol. 



Survey, p. 48. 



Used as a subgenus by Clarke. Notes on the genus Acidaspis, 1892, 

 p. 9; for species with two recurved spines of great size on the 

 occipital ring, Dicranurus hamatus Conrad. 

 Ancyropyge n. subgen. Clarke, 1892. Note on the genus Acidaspis, 



p. 9. 

 Used as a subgenus to Ceratocephala, type Acidaspis roemingeri Hall. 



ANCHORALIS Miller, 1875; Cincinnati Quart. Jour. Sci., vol. 2, p. 



349, figs 2-4. cf. Acidaspis ceralepta. Hudson. 



Ceratocephala (A cidaspis) anchor alls Clarke, 1892. Note on Acidaspis, 



pp. 11 and 12, syn. to Ceratocephala ceralepta. 

 armatus. (See Acidaspis eriops.) 



CALLICERA Hall, 1888; Pal. New York, vol. 7, pp. 69, 224, pi. 16 b, 



figs. 1-3. Clarksville, N. Y. Upper Helderberg. 



Ceratocephala (Odontopleura) CALLICERA Clarke, 1892. Note on Aci- 

 daspis, p. 13. 



Ceratocephala CERALEPTA Anth., 1838; Am. Jour. Sci., 1st series, 

 vol. 34, p. 379; figs. 1-2. Cincinnati, Ohio. Hudson. 

 CERALEPTA Meek, 1873; Pal. Ohio, vol. 1, p. 169, pl. 14, figs. 8-9. 



