THE PERMIAN FISHES OF NORTH AMERICA 



169 



Megalichthys nitidus (Cope). (Plate 30, figs. 1-4; plate 31, figs. 3-35.) 



1880. Ectosteorhachis nitidus Cope, Proc. Amer. Philos. Soc, xix, p. 56. 



1888. Ectosteorhachis nitidus Cope, Trans. Amer. Philos. Soc, xvi, p. 286. 



1891. Megalichthys nitidus (Cope), Proc. U. S. Nat. Mus., xiv, p. 457, pi. xxxii, figs. 8, 9. 



1891. Megalichthys nitidus (Cope), Woodward, Cat. Fos. Fishes, Brit. Mus., 11, p. 388. 



1899. Parabairachus nitidus (Cope), Hay, Amer. Nat., xxxiii, p. 788. 



Type: Head and trunk, including ventral fins, of a large fish. No. 7239 

 Am. Mus. Texas. 



Referred specimen: Cranium and some vertebra. No. 7936 Am. Mus. 

 Archer County, Texas. 



The principal points in the specific diagnosis may be condensed from 

 Cope's original description as follows: 



Original description: "Pectoral fins originate further behind the head than 

 is usual. The ventrals are well posterior and close together. * * * The 

 orbits are in front of a transverse line divid- 

 ing the skull equally. The muzzle is broadly 

 rounded, and is covered with rounded plates 

 of ganoine. Several of these have median per- 

 forations. * * * The top of the head behind 

 the muzzle is entirely without ganoine layer in 

 two specimens; its surface is smooth, or weakly 

 finely ridged. On the other hand the premax- 

 illary, maxillary, mandibular, and gular bones 

 are invested with perfectly smooth ganoine. 



"The pectoral fins are quite wide, and 

 their rays diverge exclusively from the inner 

 border, and are very fine. The axial portion 

 is thick and acuminate, and has no fulcra on 

 the external edge, but is covered with quad- 

 rate and rhomboidal scales, of very much 

 smaller size than those of the body. The axial portion of the ventral fins 

 is not quite so large as that of the pectoral. 



"The scales of the body are quite large and overlap each other by both 

 the free edges. Though their form is rhombic, the apex is rounded. The 

 surface is ganoid, and entirely smooth. There are five rows between the 

 internal bases of the ventral fins, and twelve between the external bases 

 of the pectorals." 



Megalichthys ciceronius (Cope). 



1883. Ectosteorhachis ciceronius Cope, Proc. Amer. Philos. Soc, xx, p. 628. 



1888. Ectosteorhachis ciceronius Cope, Trans. Amer. Philos. Soc, xvi, p. 286. 



1 891. Megalichthys ciceronius (Cope), Woodward, Cat. Fos. Fishes, Brit. Mus., 11, p. 388. 



1891. Megalichthys ciceronius (Cope), Proc. U. S. Nat. Mus., xiv, p. 457. 



1899. Parabairachus ciceronius (Cope), Hay Amer. Nat., xxxiii, p. 788. 



1900. Megalichthys ciceronius (Cope), Wellburn, Proc. Yorkshire Geol. and Poly- 



technic Soc, p. 60. 



This species was founded on two imperfect crania, which have thus 

 far not been identified among the material in the Cope collection in the 

 American Museum; nor have they been found in any other collection. 

 Cope's diagnosis of the species was as follows: 



Original description: "The E. ciceronius differs from the E. nitidus 

 in having a narrower interorbital region, and in the possession of small 



Fig. 53. — Gular plates of Mrgalichthys 

 nitidus (Cope); diagrammatic. 



