GEOLOGY AND PALEONTOLOGY. 199 
Certainly the large size of the radial process, its position on the ventral side of 
the bone, the strong curvature of the shaft of the bone, and its less expansion 
distally, are all characters inconsistent with the Cheloniide. (See Wieland, 
Am. Jour. Sci., 9: 413, 1900.) 
The remarkably complete specimen upon which this genus and species are 
based was collected by Mr. E. H. Sellards, of the paleontological department of 
the university, on the Saline river, in Trego county, the past summer. I wish 
also to express my thanks to Prof. J. T. Shearer, of Wa Keeney, for kind assist- 
ance in the collection of the specimen. 
For the sake of comparison, I give a figure, natural size, of the upper view of 
Toxochelys latiremis, made from an unusually well-preserved specimen in the 
university museum, collected by Mr. H. T. Martin, in Logan county, Kansas. 
EXPLANATION OF PLATES. 
The following explanation applies to the first three plates: pm, premaxillary ; 
mx, Maxillary; pf, prefrontal; j7, frontal; pof, postorbito-frontal; pa, parietal ; 
jor ju, jugal; g, quadrate: v, vomer; pl, palatine; pt, pterygoid; bs, basisphe- 
noid; bo, basioccipital; gj, quadratojugal. 
Plate XVIII. Voxochelys latiremis Cope, natural size. 
Ss XIX. Porthochelys laticeps Will., natural size. Fig. 1, dentary; fig. 2, 
cranium. 
ae XX. Porthochelys laticeps Will., natural size. 
oe XIX. Porthochelys laticeps Will., upper view of carapace, two-ninths 
natural size. 
«© XXII. Porthochelys laticeps Will. Fig. 1, ventral view of right hu- 
merus, three-fourths natural size; fig. 2, plastron, two-ninths 
natural size: e€, epiplastron; ip, hyoplastron; App, hypoplas- 
tron; xp, xiphiplastron. 
GEOLOGY OF THE GLASS MOUNTAINS OF WESTERN OKLAHOMA. 
BY MARK WHITE, SOUTHWEST KANSAS COLLEGE, WINFIELD. 
Read before the Academy, at McPherson, December 28, 1899. 
During the summer of 1899, the author, in company with his brother, Mr. 
Paul J. White, made a hasty trip to the Glass mountains. During this trip the 
material for this paper was collected. The author does not claim for this paper 
a high grade of science work, but a mere sketch of the Glass mountains, and of 
the geological formation found there. 
From the northeast, as first viewed by us, the Glass mountains may be seen 
for about thirty miles. They are situated in the southwest to central south part 
of Woods county, Oklahoma, and cover a territory extending south from the 
Cimarron river for a distance of six or eight miles and in width four or five miles. 
Strictly speaking, the Glass mountains are hardly worthy of the name of moun- 
tains, as evidently they are but what is left by erosion of a portion of the Upper 
Cretaceous. The first peak to which we came from the east, and which is called 
by the cattlemen ‘‘The North Peak,’’ is about ten miles southwest of Cleo, 
Woods county, Oklahoma. We crossed the Cimarron river by fording at Cleo. 
The stretch of country from this place to the mountains is a level alkali plain, 
with but little vegetation except mesquit and sage-brush. The plain reaches to 
the very foot of the mound, which is about 200 feet in altitude and almost circu- 
lar. To the south of this mountain is one covering much more space, but it is 
