114 HAY—VERTEBRATES OF CARBONIFEROUS AGE. [March 16, 
STREPSODUS DAWSONI sp. nov. 
Rhizodus lancifer, in part, Dawson, J. W., Acadian Geology, 
1868 and 1878,'p. 210, Fig.’ 56” (not a). 
In his Acadian Geology, as cited above, first in 1868, Principal, 
afterwards Sir William, Dawson identified, with doubt, some teeth 
which had been found in the deposits of the coal-measures at Pictou, 
Nova Scotia, with similar teeth which had been described by Dr. J. 
S. Newberry from the coal-measures of Ohio. Found in the same de- 
posits at Pictou were many scales, and these too were regarded as be- 
longing tothe same species. Dr. Newberry also had found some large 
scales in the deposits at Linton, Ohio, which furnished the teeth, 
and these scales, he thought, might have belonged to the animals 
which had borne the teeth. It is quite evident, however, that the 
scales found in the two localities were not the same; and it is far 
from certain that the teeth are not those of Batrachia. And even if 
the Acadian teeth are those of fishes, there is no proof that they and 
the scales belong to the same species oreven genus. Hence, it ap- 
pears to be better to allow the teeth to stand on their own merits 
and to give the scales a name of their own. 
From the Peter Redpath Museum I have received also a scale, 
No. 3076, which has every appearance of being the one which fur- 
nished the figure published by Dr. Dawson. This scale belongs to 
the genus S¢refsodus, as defined by Mr. A. Smith Woodward, and 
I give it the name of Strepsodus dawsont. 
This scale has almost the exact dimensions of Dr. Dawson’s 
figure, although the upper, or rather the hinder, end is somewhat 
less rounded than indicated by the figure. The length is 19 mm., 
the extreme width 18 mm. As seems to be indicated by the orna- 
mentation, the inner surface is exposed to view. Nearer the ante- 
rior than the posterior end is a small elongated boss, or protuber- 
ance, a characteristic of the genus. The surface of the scale behind 
this is marked by numerous little pits. Dr. Dawson’s figure repre- 
sents these pits as existing also in front of the boss, but I find none 
there. They appear to be arranged somewhat in rows, which radiate 
from the boss to the hinder edge of the scale. All around the scale, 
but less distinct on the anterior end, there is a rather wide border, 
which is occupied by undulating and concentric lines of growth. 
In this border there is, on one side, an interruption in the course 
of these lines, as though the scale had been crumpled. Dr. Dawson’s 
