 Mastodonsaurus and other similar animals were referred to as labyrinthodonts , named like Labyrinthodon for teeth that were highly folded in cross section . Owen 's " Labyrinthodon Jaegeri " was later found at Guy 's Cliffe , England by paleontologist William Buckland . Other specimens were found in the red sandstone of Warwickshire . As more fossils were uncovered in England , Owen depicted these labyrinthodonts as the " highest " form of batrachian and compared them to crocodiles , which he considered the highest form of reptiles . He also noted the large labyrinthodonts of the Keuper ( a unit of rocks that dates to the Late Triassic ) were younger than more advanced reptiles in the Magnesian and Zechstein , which are Late Permian in age . Owen used these fossils to counter the notion that reptiles evolved from a sequential progression from early amphibians ( what he called " metamorphosed fishes " ) . 
 Mastodonsaurus and other similar animals <a href='uninflect' title='1'><mark>were</mark></a> referred to as labyrinthodonts , named like Labyrinthodon for teeth <a href='null_relcl' title='2'><mark>that</mark></a><a href='uninflect' title='3'><mark>were</mark></a> highly folded in cross section . Owen <a href='null_genetive' title='4'><mark>'s</mark></a>" Labyrinthodon Jaegeri " was later found at Guy <a href='null_genetive' title='5'><mark>'s</mark></a>Cliffe , England by paleontologist William Buckland . Other specimens <a href='uninflect' title='6'><mark>were</mark></a> found in the red sandstone of Warwickshire . As more fossils <a href='uninflect' title='7'><mark>were</mark></a> uncovered in England , Owen depicted these labyrinthodonts as the " highest " form of batrachian and compared them to crocodiles , which he considered the highest form of reptiles . He also noted the large labyrinthodonts of the Keuper ( a unit of rocks <a href='null_relcl' title='8'><mark>that</mark></a><a href='uninflect' title='9'><mark>dates</mark></a> to the Late Triassic ) <a href='uninflect' title='10'><mark>were</mark></a> younger than more advanced reptiles in the Magnesian and Zechstein , which <a href='drop_aux' title='11'><mark>are</mark></a>Late Permian in age . Owen used these fossils to counter the notion that reptiles evolved from a sequential progression from early amphibians ( what he called " metamorphosed fishes " ) . 
Mastodonsaurus and other similar animals was referred to as labyrinthodonts , named like Labyrinthodon for teef was highly folded in cross section . Owen  " Labyrinthodon Jaegeri " was later found at Guy  Cliffe , England by paleontologist William Buckland . Other specimens was found in the red sandstone of Warwickshire . As more fossils was uncovered in England , Owen depicted these labyrinthodonts as da " highest " form of batrachian and compared em to crocodiles , which he considered tdahighest form of reptiles . He also noted thdaigass labyrinthodonts of thedauper ( a unit of rocks date to the dae Triassic ) was younger than more advanced reptiles in the Mdaesian and Zechstein , which Late Permian in age . Owen used these fossils to counter the notion that reptiles evolved from a sequential progression from early amphibians ( wht he called " metamorphosed fishes " ) .