THE CARBONIFEROUS PERIODS 



487 



M. 



unevenly spaced, conical (labyrinthine) teeth, no neck, and a thickset 



body with broad, five-toed feet that were probably webbed. The tail 



was flattened vertically. Even with its 



roofed skull, Eryops would not look 



unlike an overgrown modern Japanese 



giant salamander, since the bones of 



the skull were covered with skin. It - * 



was able to crawl clumsily and slowly / 



over the land, but must have been far 



more at home in the water. That this jfe 



clumsy, small-brained beast should be # 



one of the highest types of living beings y- 



of its time may help us to realize how 



remote the period was, and to what A 



an extent vertebrate life has been -"* ^ ^ J "; 3d 



,1-1 Fig. 462. — Cross section of the 



evolved since then. _ tooth o * a Stggocgphalianm Note 



Some of the Carboniferous StegO- complicated labyrinthine structure. 



cephali were armored and some had 



no protection; some had skulls nearly two feet long, while the 



skulls of others were not larger than one's thumb-nail; some had 



stout limbs, while the limbs of others were atrophied and the body 



elongated and snakelike. 



Fig. 463. — Top view of the skeleton of Eryops, a Permian Stegocephalian. The head 

 is covered with the thick, bony plates characteristic of the order. 



The commonest amphibian of the Carboniferous, Branchiosaurus 

 (Fig. 464), did not differ greatly in appearance and habits from those 

 of to-day. The teeth were small and conical, the eyes were protected 

 by a movable ring of bony plates, and the lower surface of the body 



