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134 Bulletin American Museum of Natural History
[Vol. LIX
NON-LABYRINTHODONT REMAINS ASCRIBED TO THIS GROUP
Moodie (1916) assigns Dendrerpeton and Platystegos (Dawson,
1895) of the Joggins erect trees to the labyrinthodonts. I am not personally
familiar with this material. However, Dawson figures the vertebrae
of Dendrerpeton; they are holospondylous and cannot pertain to a
member of the present group. In Platystegos the vertebrae are described
as " biconcave "; it is probable that had they been of embolomerous type
(and thus in contrast to those found in the better-known forms from the
tree stumps) their peculiar structure would have been noted by Dawson.
There is nothing in Dawson's description of the skull (it has not been
figured) to show that is a labyrinthodont. Indeed, as far as the
description goes, it might well apply to Stegops, of the Linton fauna,
which is apparently an aberrant branchiosaur.
REPTILIA
It is obvious that the evolution of the reptiles must have been under
way at the time when the Linton cannel was being formed, for the
deployment of the group was already far advanced when our next
glimpse of tetrapods is obtained in the Round Knob Formation, some-
Fig. 25. Vertebra of Spondylerpeton, X 1.
what later in the Pennsylvanian series of the same region. Remains of
reptiles, however, would not normally be expected to any extent in a
pool deposit of this sort. One form from Linton-"Eosauravus "-is
generally recognized as a reptile, and there are a very few additional
specimens which may be placed in this category.
Tuditanus punctulatus Cope
T. punctulatus COPE, 1874, pp. 271-272; 1875, p. 392, P1. xxxiv, fig. 1; 1896,
p. 303; MOODIE, 1916, pp. 85-86, Fig. 19.
Isodectes punctukatus CoPE, 1897, pp. 88-90, P1. iII, fig. 3; WILLISTON, 1908,
pp. 395-400; MOODIE, 1909a, pp. 11-16, Pls. iv, v.
'See Dawson'8 "Air Breathers," 1863, etc.