DERMATEMYDID&. 23 3 
Genus COMPSEMYS Leidy. 
Little-known turtles belonging probably to the Dermatemydidz. Free surfaces of the 
bones of carapace and plastron ornamented with small, close-set, enameled tubercles which 
produce the appearance of shagreen. Neurals hexagonal, with the broader end forward. 
Costals without distal prolongations into the peripherals. Sulci thread-like. The plastron 
suturally articulated with the contiguous peripherals and sending up axillary and inguinal 
buttresses to the costals. No evidenees of mesoplastra. Inframarginal scutes probably on 
the bridges. Vertebral scutes not greatly expanded. - 
Type: Compsemys victus Leidy. 
The genus Compsemys was establisht in 1856 by Professor Leidy, to receive the scanty 
remains which he named Compsemys victus. Later discoveries have added little to our 
knowledge regarding the genus; altho it is evident that it is represented over a wide area of 
territory and thru a eoieidceble range of deposits, having been reported from levels rang- 
ing from the Judith River beds to the Denver The only characterization that Leidy gave to 
his genus is exprest in the following words: 
The peculiarity of the specimens which has led to the proposal of the genus consists in their exterior 
surface being closely studded with uniform granular tubercles, which give to them a shagreened appear- 
ance, quite different from anything I have had the opportunity of seeing in other turtles. 
At a later time Professor Cope assigned to Compsemys Leidy’s Emys obscurus and after- 
wards returned it to Emmys. At the same time he referred to Compsemys his own Adocus 
lineolatus without explanation. These two species undoubtedly belong elsewhere. The 
same verdict must be pronounct regarding the three species described by Cope in 1875 and 
1876, from the Judith River beds, ane called by him Compsemys ogmius, C. imbricurius, 
and C. vartolosus. In 1877 Cope described his Compse mys plicatula from the Jurassic of 
Colorado, and there can be little doubt that his generic reference of the specimen was based on 
the similarity of the sculpture to Leidy’s species. Especially since Dr. Baur’s description of 
Cope’s C. plicatula it has been regarded as representing the characters of Compsemys. How- 
ever, there can be no doubt that c phieatala belongs to a wholly different genus from wrcta, and 
to another superfamily. Most of the references in scientific literature to the genus Compsemys 
(for which see the writer’s Bibliography and Catalogue of Fossil Vertebrata N. A., 1902, 
p- 437) are to the genus as typified by C. plicatula and are therefore to be tranaferied to 
Glyptops. When Baur (Proc. Acad. Nat. Sci. Phila. 1891, p. 412) states that the Laramie 
forms of Compsemys show all the characters of the Jurassic form he seems to have had in mind 
Cope’s Compsemys variolosa, but this certainly has no mesoplastron. 
So far as at present known the only species to be assigned with any certainty to this genus 
is the type, C. victa. It is probable that when the Foran that has been reported to occur in 
the Judith River beds is better known it will prove to be a second species. 
Compsemys victa Leidy. 
Plate 34, figs. 2, 3; text-figs. 292-295. 
Compsemys victus, Leipy, Proc. Acad. Nat. Sci. Phila. 1856, p. 312; Trans. Amer. Philos. Soc., x1, 
1860, p. 152, plate vi, figs. 5-7.—Coprr, Trans. Amer. Philos. Soc., x1v, 1869, p. 124; Seventh Ann. 
Report U. S. Geol. Surv. Terrs., 1873 (1874), p- 454; Bull. U.S. Geol. Surv., 1, No. 2, 1874, p. 303 
Vert. Cret. Form. West, 1875, pp. 91, 261, plate vi, figs. 15,16; ?Brit. N. A. Bound. Comm. Report, 
1875, pp- 333, 330; ?Bull. U. S. Geol. Surv., 111, 1877, p. 573.— ?Cross, Monogr. U. S. Geol. Surv., 
XXvII, 1896, p. 227.—?Marsu, Monogr. U.S. Geol. Surv., xxvu, 1897, p. 527.—Hay, Bibliog. and 
Cat. Foss. Vert. N. A., 1902, p. 437- 
Professor Leidy’s type of the present species consisted of a neural; a considerable portion 
of a costal, regarded as a fifth; and a fragment of the eighth costal. These are now in the 
U.S. National Museum and bear the aimier g6o. They were secured in deposits of probably 
Laramie age, at Long Lake, North Dakota. The species was afterward reported by Cope 
from supposed Laramie deposits in Colorado, now regarded as Arapahoe or Denver (Cross, 
op. cit., pp. 227, 244), and with doubt from Judith Rin er beds (Cope’s Fort Union) and from 
