CARBONIFEROUS LABYRINTHODONT 569 
contained five more trunk-vertebra, besides three others which were 
caudal. Dr. Plieninger seems inclined to think that all these cervico- 
dorsal vertebrae belonged to one animal: but even the fact that 
seventeen vertebra were found together in one block, and the existence 
of caudal vertebra, must be amply sufficient to satisfy every anatomist 
of the untenability of the hypothesis that the Labyrinthodonts were 
frog-like or toad-like in form. 
The trunk-vertebree of J/astodonsaurus are biconcave, and much 
flattened from before backwards. The neural arch ends above in a 
strong spinous process ; there are well-developed zygapophyses, and 
the stout transverse processes exhibit a division into an upper longer 
and a lower shorter portion. So far they are very similar to those of 
Anthracosaurus. Vhe ribs again are strikingly similar to those of 
sluthracosaurus, as may be seen by comparing plate 5, figs. 1 & 2 of 
the work cited with fig. 2, B. 
On the other hand, the vertebrae of .Wastodonsaurus, according to 
Plieninger, presented characters which I do not meet with in 
dnthracosaurus. Thus, the articular surfaces of the bodies of the 
vertebra of the Triassic Amphibian are inclined towards one another 
superiorly, while those of dzthracosaurus are parallel ; and the upper 
and lower portions of the transverse process, which are said by 
Plieninger to be separated by a suture, so that the neural arch, with 
the upper longer transverse processes, readily separates itself from the 
body with the lower and shorter transverse processes, are, so far as I 
can observe, perfectly continuous in the Carboniferous Amphibian. 
Double transverse processes, the upper more particularly connected 
with the neural arch, and the lower with the body of the vertebra, are 
to be found, though the circumstance does not seem to have received 
much notice from paleontologists, in several genera of Saurobatrachia, 
or Salamandroid Amphibians. 
In Salamandra maculosa, for example, each cervico-dorsal vertebra, 
except the atlas, has, on each rib, a prominent transverse process 
inclined backwards ; and all these processes, except perhaps the very 
last, are deeply bifid, so as to be divided down nearly to their origin 
into two more or less divergent processes. The upper division comes 
off distinctly from the neural arch, while the lower arises for the most 
part below the level of the upper margin of the articular face of the 
body of the vertebra. The transverse processes of the three or four 
anterior caudal vertebre are also bifurcated at their ends, and at the 
eighth or ninth caudal the transverse processes cease to be 
distinguishable. 
The proximal ends of the four anterior pairs of ribs are divided 
