170 MEMOIRS OF THE CARNEGIE MUSEUM 
radial sesamoid. ‘The centrale is of the same size and shape as that in the manus 
of Cynomys. 
Metacarpal ITT. is the longest of all the metacarpals; this is also true in the 
manus of Cynomys, Aplodontia, and other Sciwromorphs. he fifth metacarpal in S. 
barbourt is short and heavy, like that of S. fossor. The first digit in the type is 
parallel with the long axis of the foot, and supports a short, but well-formed ungual 
phalanx. 
The ungual phalanges are, as in S. fossor, of unusually large size. Their shape is 
entirely different from that in Cynomys or Aplodontia. The latter genera have the 
unguals transversely compressed and high, while S. barbowrt and S. fossor have them 
depressed and broad, suggesting the mole in this respect. The manus of Geomys 
has also similarities to that of S. barbowrt and S. fossor. 
The Hind-Limb. — Part of the pelvis and the left hind limb is preserved in the 
type of this species. The supra-iliac border of the pelvis is relatively broader, and 
has a more outward projecting hook in S. barbouri, than in S. fossor. In the type, 
the acetabular border of the ilium is sharp, and turns abruptly outward near the 
suprailiac border, forming the hook referred to above. 
The Femur. — The head of the femur is in position in the acetabulum, and is ap- 
parently well rounded with a rather short neck. The great trochanter is quite 
strong, and the lesser trochanter is relatively as large as in S. fossor. The bone is 
injured in the region of the third trochanter. Distally, the femur is also imperfect. 
There is a weathered fragment of bone in the rotular groove, which is of about the 
right size to be the patella. 
Tibia and Fibula. —'The relative size of the tibia and fibula is approximately 
like that of S. fossor. In the type the delicate fibula is in position and is partially 
imbedded in the matrix. So far as can be judged from the view obtained, the 
fibula appears to be free asin Cynomys, Aplodontia, and the Sciwromorphe in general. 
The Pes. —The tuber of the calcaneum in the type is comparatively longer than 
in S. fossor. The pes as a whole has the same relative size to the manus as in 
Aplodontia. Unfortunately the pes is injured in the region of the phalanges. The 
proximal phalanx of the pollex is present, and its distal articulation indicates that 
there was a fairly large ungual phalanx. ~The proximal and median phalanges of 
the third digit are broad and depressed like those of S. fossor. 
MEASUREMENTS. 
Total length of the animal, approximately...............6..c2:ccceeecee cece eeceeec ee cceeesnereeeeeeneeeeeues 25 em. 
Keng thiolicervicalirepionsapproximateliyaasscnesecnsescsckeeecioesecceeesesceecee rea csseeeesceaceseces 12) mm. 
NETS) ENE cS horpecosn aasansconsenepssoccpebedocd’ cones coldaDond Gsancenchcssoocecn asses npanno=ondedondebosabueKeGd 30 ae 
