Permian of New Mexico. 379 



ity of the Gallinas mountains, east of the Nacimiento moun- 

 tains, reaching as far east as the peak El Cobre north of the 

 Chama river. They overlie the Carboniferous, apparently 

 confonnably ; and are overlain by the Morrison beds of the 

 Jura-Cretaceous, with more or less of the .Trias doubtless inter- 

 vening. The Permian fossiliferous strata are in the lower part 

 of the Red Beds and are several hundred feet in thickness. 

 The matrix in which the fossils are enclosed is variable, con- 

 sisting of red, white, and reddish brown sandstones, and red 

 and black clay. There is an entire absence of all concretionary 

 material and pebbly conglomerates, both of which are highly, 

 characteristic of the Texas deposits. 



In the examination of these Permian fossils preserved in 

 the Yale Museum I have distinguished with more or less assur- 

 ance at least ten genera of amphibians and reptiles ; I found 

 no trace whatever of fish remains. These genera are : JSotho- 

 don Marsh, indistinguishable, from Diadectes Cope, published 

 ten days earlier ; Sphenacodon Marsh, the type of which is 

 indistinguishable from Dimetrodon Cope, published five days 

 later ; Ophiacodou Marsh, closely allied to the genus which Case 

 has called Theropleura Cope on somewhat questionable evi- 

 dence ; Eryops Cope, a species of which was described by 

 Marsh as Opkiacodon grandis ; Glepsydrops Cope, represented 

 by very characteristic limb bones ; "Dimetrodon''' navajoicus 

 Case, not a true Dimetrodon, but a short-spin ed Pelycosaur, 

 probably belonging to a new genus ; Dimetrodon Cope, repre- 

 sented by very characteristic specimens either closely allied to 

 or identical with species from Texas ; u Ctenosaurus''' rugosus 

 Case, which is not a real Ctenosaurus v. Huene from the Trias 

 of Europe, but a new genus which I shall describe and figure 

 later as Platyliistrix, gen. nov.; a pelycosaurian reptile with 

 long flattened spines, probably new ; one or two other reptiles 

 which I cannot at present determine ; Aspidosaurtis represented 

 by a new species which I shall describe as novamexicanus ; and 

 the genus Limnoseelis herein described. In addition, Case has 

 named the genera Elcabrosanrus (melius Elcobrosaurus) and 

 D iasparactus from vertebrae in the Cope collection. 



In this examination I was especially struck by the absence 

 of forms characteristic of the Upper or Clear Forks division of 

 the Texas Permian, such as the Pariotichidae, and especially 

 Labidosaurus, Diploeavlus, etc. Diplocaulus may not be a 

 characteristic guide fossil, because of its occurrence in the 

 Illinois beds that are probably lower than the Wichita division, 

 but the Pariotichidse are reliable. Not onlj is there an absence 

 of forms characteristic of the Clear Fork division, but forms 

 such as Diadectes and Clepsydrops have never been found in 

 Texas in the upper beds. The evidence thus seems to indicate, 



