CHAPTER XX. 



THE MICROSAURIAN FAMILY MOLGOPHlDyC, FROM THE COAL MEASURES OF OHIO 



AND MAZON CREEK, ILLINOIS. 



Family MOLGOPHID^ffi Cope, 1875. 



Cope, Geol. Surv. Ohio, 11, pt. 11, p. 357, 1875. 

 Cope, Bull. U. S. Nat. Mus., No. i, p. 11, 1875. 



Type of family : Molgophis. 



Body long, serpentine, a few species apparently limbless, ribless, and with 

 abdominal armature lacking. Vertebrfe elongate, neural and hasmal spines short 

 or absent. Ribs long, heavy, and broad. The vertebra} seem to bear the charac- 

 teristic marks of the family. One species has the skeleton reduced to a lanceolate 

 skull and a string of about 50 slender vertebrae, all the rest of the skeleton being 

 absent. The family is very poorly known, but was apparently of wide distribu- 

 tion in North America and confined to this continent. The representatives of 

 the group are known from Iowa, Illinois, and Ohio. 



Four genera are assigned to the family, but futtire discoveries will vmdoubtedly 

 demand revision of the present classification. The genera are Molgophis, Pleu- 

 roptyx, Phlegethontia, and Erpetobrachium. The distinguishing characters of these 

 genera are apparent from the descriptions of the various forms. The skeletons of 

 the species are too incompletely known to allow the establishment of a tabular key 

 to the genera. 



Genus MOLGOPHIS Cope, 1868. 



Cope, Proc. Phila. Acad. Nat. Sci., p. 220, 1868. 

 Cope, Trans. Amer. Phil. See., xiv, p. 20, 1869. 

 Cope, Geol. Surv. Ohio, n, pt. 11, p. 368, 1875. 

 Cope, Trans. .'Xmer. Phil. Soc., xv, p. 263, 1874. 



Type: Molgophis macrurus Cope. 

 Cope (123) gives the following: 



"The characters of this genus are: body long, serpentine, without dermal armature, 

 so far as known; vertebras long and broad, with very prominent zygapophyses and moder- 

 ate neural spines; ribs large, curved. No limbs or cranium can be ascribed to the type of 

 the genus. The ribs are long, and though the head is not bifurcate, there appears to be 

 both tubercle and head on the dilated extremity. Where crushed they display a large 

 median vacuity. 



"This genus differs from Ophiderpeion Huxley (334) in the characters of the dorsal 

 vertebrae, which, in their projecting zygapophyses, resemble those of Amphiuma. The 

 lack of ventral armatiu-e distinguishes it from CEstocephalus, while its well-developed ribs 

 separate it from Phlegethontia." 



Molgophis macrurus Cope. 



Cope, Proc. Phila. .\cad. Nat. Sci., p. 220, 1868. 



Wyman, Am. Jour. Sci. and Arts, p. 11, fig. i, 1858 (refers to a batrachian reptile). 



Cope, Trans. Amer. Phil. Soc., xiv, p. 20, 1869. 



Cope, Trans. Amer. Phil. Soc., xv, p. 263, 1874. 



Cope, Geol. Surv. Ohio, u, pt. 11, p. 368, pi. xliii, fig. i, 1875. 



Type: Specimen No. 8617 G, American Musevmi of Natural History, collec- 

 tion of Dr. J. S. Newberry. 



Horizon and locaUty: Linton, Ohio, Coal Measures. 



147 



