Case : Vertebrate Fossils from Pittsburgh, Pa 



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There are recognizable vertebrae, ribs, and intercentra of Amphibia; 

 teeth and chevron bones from Diadectid forms ; a fragment of a spine 

 probably belonging to the genus Naosaurus ; and an ilium and frag- 

 ments of a large pelvis from some undetermined forms. With the ex- 

 ception of Bathygnathus from Prince Edward Island these bones are 

 from the easternmost locality known for Permian (?) vertebrates. Tn 

 general the collection resembles rather those from Texas than those 

 from Illinois, but the specimens are far too few to base any generali- 

 zations as to distribution upon them. 



The specimens are described in detail below. 



Amphibia. 



Eryops. — A dorsal vertebra is very probably from this genus (Fig. 

 i). The specimen consists of a nearly perfect vertebra, lacking only 

 the anterior zygapophyses and the upper portion of the neural spine. 

 It shows no character that would warrant its separation from the genus, 

 and indicates a medium-sized individual. The 

 zygapophyses are well formed with clean-cut 

 articular faces. The pleurocentra are thickened 

 above with well-defined articular faces, which 

 were applied to faces on the neural arch just 

 posterior to the origin of the transverse process. 

 The intercentrum is of the familiar half-moon 

 shape, thick and heavy below, and thinner 

 toward the extremities ; the anterior edge is 

 marked near the top by the indentation found 

 on the intercentra of Eryops. 



Height of the vertebra from the middle of 

 the lower face of the intercentrum to the 

 middle of the neural canal .035 m. Width 

 of intercentrum .026. 



The second recognizable specimen is a 

 neural spine from the caudal series (Fig. 2). 



This is without question a portion of the skeleton of an Eryops. 

 Similar spines were described by Cope as Eryops (Epicordylits) 

 erythroliticus, but later discoveries seem to show that similar characters 

 occur in other species of the genus as well. The apex of the spine is 

 bifurcate, the space between extremities is concave and perfectly 

 smooth ;. below the sides of the spine are rather rugose and marked 



Fig. 1. Dorsal verte- 

 bra of Eryops. Left 



