ACR. ASP.] 



PISCES. 



587 



Geo. Sur. 111. vol. 2, p. 116, St. 

 Louis Gr. 



rectus, St. John & Worthen, 1883, Geo. 



Sur. III., vol. 7, p. 241, Up. Coal Meas. 



xiphias, St. John & Worthen, 1883, Geo. 



Sur. 111., vol. 7, p. 244, Kokuk Gr. 

 ACROLEPIS, Agassiz, 1830, Recherches sur 

 les Poiss. Foss., vol. 2, p. 79. [Ety. 

 akros, sharp.] 

 le()is, scale; 

 Distinguished 

 from Pygopte- 

 rus in the 

 shorter anal 



FIG. lluO. Acrolepis sedg- 

 wicki. Magnified scale. 



being a little 

 more anterior 

 in position and 

 the scales mo re 

 strongly keeled and sulcated diagon- 

 ally. Tvpe.A. sedgwicki. 

 hortonensis, Dawson, 1888, Acad. Geol., 



p. 254, Subcarboniferous. 

 Agassichthys, Newberry, syn. for Macrope- 

 talichthys. 



minni, see Macropetalichthys manni. 

 sullivanti, see Macropetalichthys sulli- 



vanti. 



AQASSIZODUS, St. John & Worthen, 1875, 

 Geo. Sur. 111., vol. 6, p. 311. [Ety. 

 proper name ; odous, tooth.] Teeth 

 variable, transversely elongated, base 

 usually produced; crown traversed by 

 a crest, raised into several summits, 

 the central one often large. Type A. 

 variabilis. 



corrugatus, Newberry & Worthen, 1870, 

 (Orodus corrugatus,) Geo. Sur. 111., vol. 

 4, p. 358, Coal Meas. 



scitulus, St. John & Wortheu, 1875, Geo. 

 Sur. 111., vol. 6, p. 322, Coal Meas. 



FIG. 1101. Agassizodus variabilis. 



variabilis, Newberry & Worthen, 1870, 

 (Lophodus variabilis,) Geo. Sur. 111., 

 vol. 4, p. 361, Coal Meas. 



virginianus, St. John & Worthen, 1875, 

 Geo. Sur. 111., vol. 6, p. 321, Coal 

 Meas. 



AMACANTIIUS, St. John & Worthen, 1875, 

 Geo. Sur. 111., vol. 6, p. 464. [Ecy. 

 ami, backward ; akantha, spine.] Dor- 

 sal spine firmly implanted, curved for- 

 ward, laterally compressed, posterior 

 face truncated and longitudinally keeled 

 or denticulate along the median line ; 

 rounded and tuberculated in the con- 

 cave anterior face; lateral surface 

 covered with tuberculose costse. Type 

 A. gibbosus. 



gibbosus, Newberry & Worthen, 1866, 

 (Homacanthus gibbosus,} Geo. Sur. 111., 

 vol. 2, p. 1 13, SD. Louis Gr. 

 AMBLYPTKRUS, Agassiz, 1833, Recherches sur 

 les Poissons Fosses, t. 1, p. 28. [Ety. 

 hmhlys, blunt; ptero, fin.] All fins 

 large and composed of numerous rays; 

 pectoral very large; anal hrrnd; dorsal 

 opposite the anal point of the ventral, 

 which is far back ; little rays on the 

 superior lobe of the heterocercal tail ; 

 head blunt; scales medium, rhomboid. 

 Type A. macropterus. 



macropterus, Agassiz, 1836, R'cherch. 



Poiss. Foss., vol. 2, p. 28, Coal Meas. 

 ANACMTACAXTHUS, St. John & Worthen, 

 1875, Geo Sur. Ill , vol. 6. p. 442. [Ety. 

 annkWos, leant upon ; akantha, spine.] 

 Fin spine recumbent or imbedded along 

 its inferior extent, laterally compressed, 

 subovate in transverse s -ction ; exposed 

 part constricted along the line*of union 

 wi'h the base. Type A. s^micostatus. 



semicostatus, St. John & Worthen, 1875, 

 Geo. Sur. III., vol. 6, p. 443, Burling- 

 ton Gr. 



ANTLIODUS, Newberry & Worthen, 18f6, 

 Geo. Sur. 111., vol. 2, p. 33. [Etv. anttia, 

 a depression ; odous, a tooth.] Teeth 

 transversely elliptical, compressed, con- 

 cavo-convex ; crown similar to that of 

 Petalodus; root short or obsolete. Type 

 A. mucronatus. 



cucullus, Newberry & Worthen, 1866, 

 Geo. Sur. 111., vol. 2. p. 41, Keokuk Gr. 



gracilis. St. John & Worthen, 1875, Geo. 

 Sur. 111., vol. 6, p. 393, Warsaw Gr. 



minutus, Newberry & Worthen, 1866, 

 . Geo. Sur. 111., vol. 2, p. 43, Keokuk Gr. 



mucronaius Newberry & Worthen, 1866, 

 Geo. Sur. 111., vol. 2, p. 38, St. Louis Gr. 



parvulus, Newberry & Worthen, 1866, 

 Geo. Sur. 111., vol. 2, p. 38, Burling- 

 ton Gr. 



perovalis, St. John & Worthen, 1875, Geo. 

 Sur. 111., vol. 6, p. 393, Warsaw Gr. 



politus, Newbetry & Worthen, 1866, Geo. 

 Sur. III., vol. 2, p. 42, Keokuk Gr. 



robut-tus, Newberry & Won hen, 1866, 

 Geo. Sur. 111., vol. 2, p. 39, Kaskaskia Gr. 



sarcnlulus, Newberry & Worthen, 1870, 

 Geo. Sur. 111., vol. 4, p. 356, Burling- 

 ton Gr. 



similis, Newberry & Worthen, 1866, Geo. 

 Sur. 111., vol. 2, p. 41, Keokuk Gr. 



simplex, Newberry & Worthen, 1866, Geo. 

 Sur. III., vol. 2, p. 44, Burlington Gr. 



sulcatus, Newberry & Worthen, 1866, Geo. 



Sur. 111., vol. 2, p. 45, Keokuk Gr. 

 APEDODUS, Leidy, 1856, Jour. Acad. Nat. 

 Sci., 2d ser., vol. 3, p. 162. [Ety. apedos. 

 level, smooth ; odous, tooth.] Flattened 

 lancet-shaped teeth. Type A. priscus. 



priscus, Leidy, 1856, Jour. Acad. Nat. Sci., 



2d ser., vol. 3, p. 162, Chemung Gr. 

 ASPIDICHTIIYS, Newberry, 1873, Ohio Pal., 

 vol. 1, p. 322. [Ety. aspis, shield; 

 ichthys, fish.] Dorso-median plate of 

 the carapace similar to that of Pte- 



