68 
THE EACES OF THE GALAPAGOS. 
The bones of t\ie foreann do not show any noteworthy peculiarity ; but, for the sake 
of comparison with the other species, I give the measurements: — The ulna has a 
length of 137 millims., and a width of 28 millims. in its narrowest part ; the radius a 
length of 121 millims,, and a circumference of 50 millims., also measured in its 
narrowest part. 
As in Testudo generally, so here the carpal bones (Plate LIII. fig. D) are arranged in 
three series, of which the proximal consists of two bones, Imiare and cuneiforme, both 
articulating with the end of the ulna {u) ; the middle, of the transversely elongate 
scaphoid and " intermedium ; " and the distal, of five small rounded^bones corresponding 
to, and articulating with, the five metacarpals. The scaphoid articulates with the end of 
the radius (r), the " intermedium " being intercalated between the lunare and third 
digit. However, in the old specimen of this species there exists the peculiarity that the 
scaphoid and intermedium are coalesced into a single very long bone [a], and that the 
two radial ossicles of the distal series are similarly united [b). 
Pelvis (Plate LII.). — In the first place must be noticed the considerable horizontal 
width of the symphysial bridge {a) between the obturator foramina, by which the flat- 
headed Tortoises are so signally distinguished from the round-headed ones. But quite 
peculiar to this species is, first, that also the vertical diameter of this bridge is consi- 
derable and scarcely less than the horizontal, and, secondly, that, although all other 
sutures in this aged specimen have disappeared, the transverse suture between the pubic 
and ischiadic halves of the bridge is still persistent. The iliac bones are comparatively 
slender, the longitudinal diameter of the pelvis much exceeding the horizontal one. 
The lower part {h) of the pubic bones is gently inclined downwards and slightly concave 
above; it emits laterally a very long, strong, nearly styliform process (c), which is 
obliquely directed outwards. The posterior part (f/) of the ossa ischii is of considerable 
width, very slightly concave above, and provided with a trenchant symphysial crest 
below, which, expanding hindward, forms a large triangular tuberosity. Lateral 
margin of the ossa ischii excised in the shape of a C. Obturator foramina of moderate 
width, considerably wider than the bridge between them, which is not provided above 
with a median longitudinal crest. 
millim. 
Longest inner vertical diameter of pelvis (from summit of ilium to symphysis) 170 
Longest inner horizontal diameter of pelvis 132 
Shortest inner horizontal diameter of pelvis (between ilio-pubic prominences) 112 
Longest diameter of foramen obturatorium 42 
Width of symphysial bridge 26 
Depth of symphysial bridge 26 
Least breadth of posterior portion of ossa ischii 61 
Length of os ilii 140 
Least breadth of os ilii 30 
The shaft of femur (Plate LIII. figs. A, A', A") is rather stout, nearly straight, 
