187.] 191 
[Cope, 
This interesting fossil was found in the Triassic formation of Texas by 
my friend Jacob Boll. The cranium and vertebre were discovered in such 
relation as render it evident that they were parts of one animal. 
STRIGILINA GURLEIANA, Cope, sp. nov. 
This species is known by a single jaw or tooth in complete preservation, 
which was found, like the type of the genus S. lingueformis* near Dan- 
ville, Il]., by Mr. Gurley. 
The tooth is quite small, its length only equaling the width of the 
known tooth of S. lingueformis. It is also narrower in proportion to the 
length. The root and the cutting edge are turned in opposite directions 
as in the other species. The principal difference between the two is seen 
in the character of the transverse ridges or crests of the oval face. There 
are two crests less, or five, with a delicate basal fold, making six, 
while, counting the fold there are eight in S. lingue#formis. The anterior 
ridge is transverse ; the others slightly convex backwards, and all are 
equidistant and uninterrupted, which is not the case in the older species. 
They are also of different form, being distinct ridges with anterior and 
posterior faces similar. In S. linguewformis the anterior face only is verti- 
cal, the posterior descending very gradually, the whole forming a series of 
steps. Length of ridged face .0060 ; width anteriorly .0035 ; width pos- 
teriorly .0020. 
This species is dedicated to William Gurley, of Danville, Illinois, to 
whose zeal science is indebted for the species from that locality described 
in this and other papers. 
Twenty species have now been obtained from the Clepsydrops shales, the 
exact geological position of which remains to be accurately determined. 
Dr. Winslow informed me that they are the bed No. 15 of Prof. Bradley’s 
section of the Carboniferous rocks of Vermilion county, [llinois. This 
places them near the summit of the Carboniferous series, below two thin 
beds of coal (which word is misprinted ‘‘ coral’’ in my last paper, Proceed. 
Amer. Philos. Soe. 1877, p. 63). I am now informed that this portion of 
Prof. Bradley’s scale is not correct, and that No. 15 occupies a much 
higher position than he assigns to it. It lies unconformably above the 
merom sandstone of Mr. Collett, which deposit is above the coal meas- 
ures and unconformable to them. The stratigraphical evidence is thus 
conformatory of that derived from paleontology, that the Clepsydrops 
shale occupies a position in the scale above the coal measures. 
CTENODUS PUSILLUS, Cope, sp. nov. 
Form narrow, the width of the base about equal to the depth. The 
coronal portion is narrower than the base, because the inner face is 
oblique, forming an acute angle with the inferior plane. There are but 
four crests, of which the two longer are directed in one direction, and the 
two shorter in another. The interior ones of both pairs form a continuous 
*Proceedings Amer. Philos. Soc, 1877, p. 52. 
