EASTMAN: CARBONIFEROUS FISHES FROM THE CENTRAL WEST. 169 
of Blue Springs, Nebraska, and is shown of the natural size in Plate 2, Fig. 
4, Inspection shows that Cope mistook the worn base of the crown for a trun- 
cate root, in allusion to which the name Styptobasis was given; and so far as 
may be judged from the form and ornamentation of the crown, it differs from 
the foregoing species merely in the fact of being somewhat more robust. The 
shallow median depression at the base of the crown on its outer face likewise 
occurs in C. occidentalis. Another Cladodont tooth, scarcely distinct from the 
latter species, is described by O. P. Hay under the name of C. girtyi, from the 
Coal Measures of Colorado. 
Formation and Locality. — Permo-Carboniferous; Blue Springs, Nebraska. 
Phoebodus knightianus, sp. nov. 
(Plate 4, Figs. 40, 40a.) 
Type. — Imperfect tooth ; Museum of Comparative Zoology. 
From the same locality as the preceding, Professor Knight secured some 
years ago one nearly perfect tooth and the root of a second specimen, which he 
cited as “ Diplodus, sp. nov.” in his faunal list of the Kansas and Nebraska 
Permo-Carboniferous.t_ Through the courtesy of their discoverer, these speci- 
mens have come into the possession of the Museum of Comparative Zoology, 
and form the basis of the following description. It is stated in a letter from 
Professor Knight that his attempt to remove some of the adherent ‘matrix 
from the more perfect tooth resulted in some injury to the latter, and the 
broken parts were unfortunately not preserved. He had, however, observed 
that the three principal cones were all of the same height, and that the base 
was symmetrically developed. Accordingly, in the figures here given of the 
fractured specimen, its original outline is restored on Professor Knight’s 
authority. 
Teeth of moderate size, the median and two outer cones of equal height, 
and no intermediate denticles. All three cusps stout and erect, convex on 
both faces, with sharp lateral carinae, and a few delicate, slightly curved striae 
extending for a short distance upward from the base. Attached surface of root 
nearly plane, with a single pad-like prominence directly underneath the median 
cone ; postero-superior surface with a rounded ‘“ button.” 
The root agrees in size and general form with that of Diplodus platypternus 
Cope, except that both the posterior button and antero-inferior prominence are 
of relatively smaller size. From Phoebodus politus Newb. and other Devonian 
species the present form is distinguished by the absence of intermediate den- 
ticles, a character in which it agrees with the Triassic P. brodiev. The type 
specimen is shown of four times the natural size in Plate 4, Figures 40 and 
40 a, but in these illustrations the anterior boss on the lower surface of the root 
1 Journ. Geol., Vol. VIL, 1899, pp. 366, 372, 374, 491. 
