♦ 
82 THE EACES OE THE GALAPAGOS. 
is nearly horizontal, the fore part of the shell being strongly compressed, concave on 
each side, with the anterior margin strongly reverted — this part of the shell having an 
appearance which has been so aptly compared by Porter to a " Spanish saddle." 
The hind part of the shell is rounded, with a steep posterior profile, but more gently 
declivous on the sides, the marginal plates above the hind legs being arched outwards 
with the edge somewhat reverted, but less so than on the anterior marginal plates. 
The anterior as well as the posterior margins are irregularly scalloped. The plates are 
nearly smooth, the areolar portions passing gradually into the striated portions ; but 
the striae themselves are inconspicuous and in many places nearly obliterated. The 
sternum * is deeply concave, truncated in front and behind, the substance of the caudal 
plates and of the lateral portion of the abdominals being much thickened. 
I need not mention the scutellation of the head and legs, none of the Galapagos 
Tortoises showing any peculiarity in this respect. The tail is very short, and without 
terminal " claw." 
On comparing the carapace of the young example with that of equally small speci- 
mens of other species, we find the areolar spaces larger, the concentric strise deeply 
sculptured, but less numerous and further apart. Especially the sternal plates are 
smooth, with the striae partly obliterated. Posteriorly the sternum terminates in a 
notch (and this appears to be uniformly the case in very young specimens of all the 
species) ; but this notch is much shallower than in T. nigrita, obtuse-angular. 
The measurements of these two specimens are the following : — 
Length of carapace. Width of carapace. Depth of Sternum. Caudal plate. 
In str. line. Over curve. In str.linc. Over curve, carapace. Length. Width. Length. Width. 
Spec. in. in. in. in. in. in. in. in. in. 
Adult 33 40 231 40 17 24 21^ 3^ 6 
Young ... 7 91 5 81 31 4f 6| 1 li 
Skull. — The skull (Plates XLII.-XLIV. fig. C) is comparatively smaller than that of 
T. elephantopus ; it is 4f inches long, measured from the front margin of the inter- 
maxillary to the occipital condyle, and of inches broad in its widest part between the 
zygomatic arches. The sutures between the various bones can be clearly traced ; and 
growth evidently had not ceased entirely — an observation confirmed by the examination 
of other bones extracted from the specimen. 1. The frontal region is flat, broad, 
passing into the very short snout, its greatest width (in front of the postfrontals) being 
about one half of the distance between the tympanic condyles. 2. The occipital crest 
is moderately developed, pointed behind, and rising but little above the level of the 
upper surface of the skull. 3, The tympanic case with the mastoid is produced back- 
wards, the hind margin of the paroccipital forming a rather strong curve (Plate XLII. 
* A large portion in the middle of the sternum has been cut out by the person who preserved the animal, 
in order to extract the contents of the shell. 
