LABYRINTHODONT BATRACHIANS. 483 
ing Batrachians, their fossil ancestors had an armor of large 
breast-plates, with smaller scales on the under and hinder 
part of the body. 
But the largest forms were the true Labyrinthodonts repre- 
sented in the Carboniferous rocks of this country by Baphetes, 
and in Europe by Anthracosaurus, Zygosaurus, and in the 
Permian beds of Texas by Eryops. Labyrinthodonts also 
abounded in the Triassic Period, and forms like the Euro- 
pean Labyrinthodon or Mastodontosaurus must have been 
colossal in size. Footprints occur in the Subcarboniferous 
rocks of this country which indicate forms still larger than 
any yet discovered in the Old World. A large number 
(thirty-four species, referable to seventeen genera) of medium- 
sized Labyrinthodonts have been described from the coal 
measures of Ohio by Cope which were characterized by 
their long, limbless, snake-like bodies and pointed heads, 
forming a still more decided approach to the Ganoids. This 
was the lowest group of Stegocephala, called Microsauria by 
Dawson. 
Thus we have in these Labyrinthodonts synthetic or an- 
nectant forms, which connect the fishes with the Am- 
phibians, and on the other hand point to the incoming of 
the reptiles. They were thus prematuritive, larval forms, 
which in certain characters anticipated the coming of a 
higher type of Vertebrate. The reptiles were ushered 
in during the Permian Period, the rocks of this age imme- 
diately overlying the coal measures, though it should be: 
stated that there are obscure traces of reptiles in the Carbon- 
iferous rocks. It is not improbable that evidence will be 
found to substantiate the impression that the reptiles, 
together with but independently of the Amphibians, 
branched off from the Ganoid fishes, or from extinct forms 
related to them. 
Order 6. Anura.—The toads and frogs represent this: 
order, which comprises tailless Batrachians, with the four 
limbs present, the toes being very long (due to the great. 
length of the calcaneum and astragalus), while the body is 
short and broad, the skin soft and smooth, scaleless, though 
small plates are sometimes embedded in it. The lower jaw is 
