PLEUROSTERNID&. 55 
been crowded out of contact with each other. The humerals measured 47 mm. at the midline; 
the pectorals, 63 mm.; the abdominals, 54 mm.; the femorals, about 78 mm. There were 
doubtless inframarginals on the bridges, but the sulci are obscure. 
Since the preceding description was written a second specimen has been made available 
for study. This was collected by Mr. Barnum Brown, in 1904, in the Crow Reservation, 
Montana, at a point about 50 miles southeast from Billings and about 25 miles east of Pryor. 
The catalog number of the specimen in the American Museum is 6071. It furnishes more of 
the shell than does the type, but unfortunately the plastron is fractured and faulted obliquely 
to its length and the carapace is fractured and faulted in several directions. 
The carapace was about 325 mm. long and the width is close to the same. The anterior 
border is preserved on each side to behind the axillary notches; it is obtuse and about 10 mm. 
thick. The surface presents the same kind of sculpture as the plastron, consisting of low wind- 
ing ridges. The sulci are rather obscure, but the vertebral scutes were broad, as in the type, 
while the right third costal is seen to have been only 70 mm. high. 
The length of the plastron appears to have been close to 295 mm. The bridge is 125 mm. 
wide. From the line joining the free borders of the anterior and posterior lobes of the plastron 
the bridge rose to the free border of the carapace, a distance of about 110 mm. The hinder 
lobe has a width of 125 mm. and a width of 110 mm. at its base. At the ends of the femoro-anal 
sulci the width is 83 mm. The hinder border confirms the accuracy of fig. 32. On the bridges 
are some indications of inframarginal scutes, too obscure to be traced. 
Figs. 33 and 34. Glyptops depressus. Specimen in U.S. N. M. 
33- Carapace of type. 3. 
34. Portion of plastron of type. 4. ax.b, axillary buttress; ent, entroplastron; epi, epiplastron; hyo, 
hyoplastron; hypo, hypoplastron; ing. b, inguinal buttress; mes, mesoplastron. 
Glyptops depressus sp. nov. 
Text-figs. 33, 34- 
The type of this species belongs to the United States National Museum. It appears to 
have been secured by one of Professor O. C. Marsh’s collectors in 188g, inasmuch as it bears 
his packing number “1998. Box 3.” With the specimen comes a statement by Mr. Whitman 
Cross, of the United States Geological Survey as follows: 
“*No. 2 Box B. ’89,’ (Cannon’s designation). An isolated fragment. (I think this fossil is 
from the Denver beds, from the nature of the sandstones between the shells and the apparently 
zeolitic material in cells of the bone.)” 
Professor Marsh has recorded Compsemys plicatula from the Denver beds, but whether on 
the evidence of this specimen can not be determined. The probabilities that the same species 
is found from the top of the Jurassic to the top of the Cretaceous are remote. ; 
The specimen presents considerable portions of the carapace and of the plastron. The 
