262 



SUPPLEMENT TO THE EXTINCT BATIiACHIA 



Group TV. Amhulatory limbs and unos.sifiecl vertebral column : Colosteus, Am- 

 pliibamus. 



Group V. Veitcbral column osseous, the branchial hyoid bones well developed: 

 Cocytinus. 



The locality from which these fossils were procured is near Linton, Columbiana 

 County, near Yellow Creek, and is thus near the Pennsylvania State line, and the 

 Ohio River. They occur in a small basin near the middle of the series, in the lower 

 part of the " diamond bed," which is eight feet in thickness, on the slate which is in 

 contract with the lower three to six inches of the seam, which is cannel coal. 



It is to be observed that the specimens are, in some cases, quite obscure, and 

 although little or nothing of a doubtful nature has been introduced into the following- 

 descriptions, yet the elements are sometimes covered by a thin layer of carbonaceous 

 matter, which prevents their entire definition. 



PHLEGETHONTIA, Cope, . ' 



Proceed. Amer. Philos. Soc, 1871, 177. 



This is one of the most interesting genera of the present series. It I'ests chiefly 

 on a single specimen of one species, which is not perfect, but which displays the fol- 

 lowing character. 



Head elongate triangular ; body and tail extremely elongate, the dorsal vertebrae 

 without ribs, and the caudals without dilated spines. ISTo ventral armature nor limbs. 



As a great portion of the length is preserved and no ventral rods nor scales are 

 visible, and as this character is confirmed by a second species, it probably belongs 

 truly to the genus. The pectoral shield is also wanting in the specimen, but, as there 

 is a considerable hiatus behind the skull of the specimen, it may be that these were 

 lost with other parts. Chevron bones are not observable on the caudal vertebras. 

 This form is a true batrachian snake. 



PHLEGETHONTIA LINEARIS, Cope. Sp. Nov. 



In the only specimen, the dorsal vertebrae are much involved anteriorly, so that the length is not readily ascer- 

 tained. The entire outline of the skull is preserved ; it is elongate triangular in form, with the angles of the man- 

 dibles produced backward and the outlines of the rami a little convex. Nothing definite remains as to sculpture or 

 dentition. The vertebras have longitu.dinal diapophysial keels, and have a zigzag interlocking of neural arches, 

 probably by an external zygosphen above the zygapophyses. The latter are distinctly turned outwards. The ver- 

 tebrae are very numerous, and the tail very attenuated. The total length of the coils unwound is about m .295 or 11 

 in. 8 lines ; but there are interruptions not measured, and some confusion not unraveled. The number of dorsal 

 vertebrae in .005 m., two ; of distal caudals, thrpe and a-half. Length of cranium, .022 ; with behind .009. Its size 

 is about that of the skull of Ptyonius marshii, Cope. The slenderness of the body may be estimated from the 

 diameter of the dor.sal vertebrae, m. .0023 ; and of the caudals .0014. The whole number of vertebrce preserved 

 is fifty-six. 



