4O THE COAL MEASURES AMPHIBIA OF NORTH AMERICA. 



reptiles was at times disputed, but no one seemed to pay any attention to the argu- 

 ment of Quenstedt in 1850 that "Die Mastodonsaurier im grunen Keupersand- 

 stein Wurtemburgs sind Batrachier" (527), nor to the contention of Vogt (581) in 

 1854 that ' ' Archegosaurus und alle Labyrinthodonten sind Amphibien, nicht Rep- 

 tilien." 



In 1842 von Meyer (420) proposed to include all the early forms allied to the 

 Mastodonsaurus in the " Labyrinthodontes. " His definition of the group follows: 



LABYRINTHODONTES : Saurier deren Zahn-Struktur jener ahnlich ist, welche in den nach prismat- 

 ischer Art gebauten Saugethier-Zahnen wahrgenommen wird, u.s.w. 



I. Mastodonsaurus Jaeger. (Salamandroides Jaeger, Batrachosaurus Fitzinger, Labyrinth- 



odon Owen.) M. Jaegeri Meyer. 

 II. Capitosanrus Mimster. 

 C. arenaceus Miinst. 

 C. robuslns Meyer. 

 III. Metopias Meyer. 



M. diagnosticus Meyer. 



Three years later von Meyer (423) proposed his "System der fossilen Saurier," 

 where the extinct Amphibia are treated as follows: 



LABYRINTHODONTES. 



1. Prosthopthalmi (Augen-hohlen in der vordern Halfte der Schadel-Lange) Metopias 



Meyer. . . . Keuper. 



2. Mesopthalmi (Augen-hohlen in der mitte der Schadel) 



Mastodonsaurus Jaeger Keuper, Muschelkalk. 



3. Opisthopthalmi (Augen-hohlen in der hintern Halfte der Schadel-Lange) Capitosaurus 



Minister Keuper. 



4. Labyrinthodonten ungewisser Stellung. 



Labyrinthodon Owen Keuper. 



Xestonhytias Meyer . . Muschelkalk. 



Odontosaurus Meyer Bunter Sandstein. 



/ 1 cnidtosaums Braun Bunter Sandstein. 



No other classification was proposed for the extinct Amphibia for 15 years, when 

 Owen (512) in 1859 proposed the new order Ganocephala and retained von Meyer's 

 Labyrinthodontes under Labyrinthodontia. Owen's classification is as follows: 



Class REPTILIA. 

 Order I. Ganocephala. 



Genera: Archegosaurus, Dendrerpcton, Raniceps. 

 Order II. Labyrinthodontia. 



Genera: Mastodonsaurus, Anisopus, Trematosaurus , Metopias, Capitosaurus, Zygosaurus, 

 Xestorrliytias. 



In his Paleontology published in 1861, Owen gives the same classification, but 

 adds new genera. 



Huxley in 1863 (332) did not accept Owen's Ganocephala, but instead proposed 

 the following: 



LABYRINTHODONTIA. 



A. Archegosauria. Archegosaurus, Pholidogaster. 



B. Mastodonsauria. Mastodonsaurus, Labyrinthodon, Capitosaurus, Trematosaurus. 



In the same year Dawson proposed (208) the term Microsauria to include the 

 genera Hylonomiis, Dendrerpeton, and Hylerpeton, all known from the Carboniferous 



