425 FOSSIL TURTLES OF NORTH AMERICA. 
The length of the carapace of this individual is 930 mm.; the greatest breadth, 690 mm. 
Thru pressure of the overlying matrix the carapace 1s somewhat ‘deprest, so that the form 
of the shell is best shown by dhe type of the species. The length of the plastron is 840 mm. 
The anterior lip projects hardly as much as in the type, a erolles individual. 
This specimen displays beautifully the armor of the forelegs. A closely compacted layer 
of bony nodules was imbedded in the skin, from the bases of the claws to the middle third of 
the upper arm bone. Along the ulnar side of the forearm is a row of larger nodules, one of 
which appears to have been formed by the co-ossification of two originally distinct bones. 
Some of the larger nodules appear at the elbow j joint. Above this the nodules decrease in size. 
The palm of the hand was protected by a layer of bones of moderate size. Beyond the bones 
forming the armor of the foot projected the five claws. 
The hind foot possest a sole of bony nodules, but those bones shown in the figure near the 
claws are the phalanges. “Toward the hinder border of the foot the nodules hecome larger 
and the two hindermost project as great spurs. Such bony spurs armed with a covering of 
tough horn would doubtless offer some discouragement to any carnivorous animal that might 
have sought entrance in that region. Perhaps also these spurs would be of assistance to the 
animal in walking over a rocky surface. Another great spur lies alongside the fourth claw 
phalange and ceraulenee a fifth claw. In the type specimen, No. 5868, the fifth tarsal bone of 
the second row shows an articular surface for a rudimentary metatarsal. 
The tail presents in general the same features as that of the type specimen. The central 
nodules are still more intimately consolidated. The lower border of the armor covering the 
tail was apparently 140 mm. wide, and was bordered by about 10 nodules, which increase in 
size from the midline each way. The outer 3 are pointed. It was probably just outside of 
these that the armor of the tail past into that covering the thighs. In this specimen this armor 
is continued two-thirds the distance to the knee-joint. On each side of the tail are two very 
large and pointed spurs, such as we find on the thigh of various living species of T estudo; but 
these in 7. osborniana appear to have been placed nearer the tail cian usual. In the type 
specimen there appears only one spur on each side of the tail. 
The scapula and its proscapular process are slenderer than those of T. impensa. The 
type of the latter has a carapace only a few millimeters shorter than the specimen of 7. oshorn- 
iana here described. The table presents the dimensions of certain parts of the two species. 
Testudo Testudo 
Measurements taken. 5 5 
impensa. osborniana. 
Diameter of procoracoid process at middle of length: 
Greater.....-. ehgoicereratatiuals : ae : 43 oi 
Smaller 27 23 
Length of coracoid fam Plesoid t to median border 155 145 
Length of median border of coracoid............ 145 16s 
Length of humerus from middle of nea to distal al 240 240 
Least diameter of shaft.............- 41 38 
The ulna is hidden beneath the armor. The right radius is exposed sufhciently to permit 
determination of the length. This amounts to 135 mm. 
The skull of this individual was considerably macerated about the time of burial; the 
bones have been more or less fractured and sometimes slightly displaced. One important differ- 
ence is shown between it and the skull of the type; namely, the interorbital space is much 
broader. Inthe type this space is 28 mm. wide; in the one now described it 1s 43 mm. Ordi- 
narily this difference would be regarded as indicating a distinct species. Here we have prob- 
ably a difference due to sex. aGhe type 1s almost certainly a male, as is shown by the very 
concave plastron. The other individual has a very flat plastron and was probably a female. 
The cervical vertebra are all present. The elements of the first are hidden beneath the 
supraoccipital process. The second has been damaged so badly that little can be said regarding 
it, but the posterior end appears to have been concave. The third seems to have had a convex 
anterior end. Its posterior end is concave. The fourth has the anterior end convex. The con- 
tiguous ends of the fourth and fifth are injured, but it seems pretty certain that the hinder end 
oF the fourth was convex and the anterior end of the fifth concave. The sixth is concave in 
