THE GALAPAGOS TORTOISES. 275 
1875, Plate 35A, from a thirty-three inch specimen, are included in Plate 7. 
Specimens at hand are more curved from the middle of the fourth vertebral 
scale to the anterior marginals than in this drawing. In the fourth vertebral 
and backward the curve is sharp, but the marginals are less declivous, which is 
also true of the forward marginals. On both front and back the marginals are 
somewhat reverted, concave on their upper surfaces, in the older specimens. 
A number of the specimens in the M. C. Z. were secured by Webster near Iguana 
Cove in the southern part of Santa Isabela (Albemarle); these are compared 
with the figures of those secured by Van Denburgh in the same locality. The 
declivity from the middle of the fourth vertebral backward is usually greater 
than that forward from the second. The caudal plate is directed downward, 
and slightly forward at the lower edge. A large shallow notch partly separates 
the marginals of the foremost pair. The indentation at the fourth, and that 
at the eighth marginal, on each side are shallow, as also the grooves, compres- 
sions, extending from them. Except perhaps on specimens of greater age, 
the concentric striae are present. The areolar spaces vary in convexity; in 
cases they are prominent. The carapace is broader posteriorly; it appears 
subtruncate, the caudal scale being indented between the marginals at each 
side of it. In front the margin is the more rounded, subacuminate. Above 
the humeral and the femoral arches the marginals form scallops. 
The sternum of the type is longer than broad; the humeral extension, 
in front of the bridge, is broad at the end and is somewhat concave on its lateral 
margins in the large specimens. The femoral extremity is shorter, broader, 
and is convex on the lateral margins of the abdominal plates. In both young 
and old the gulars thicken upward; on the aged they have a comparatively 
small amount of the downward swelling. The anal scutes are broader than the 
eulars and have an angular notch between them; they thicken and curve down- 
ward with age. The sternal concavity is deepest below the hinder portions of 
the abdominal scales; it is deeper on the old males. 
In recent collections of specimens of this species there are appearances of 
considerable mixtures by transportation from one island to another. The 
earlier captures appear more distinct than some of the later ones. Undoubt- 
edly the oil collectors, the orchilla pickers, the meat hunters and others were 
quite ready to contribute to a distribution that has left traces in various direc- 
tions, and latterly the young specimens from different islands have been on 
sale within reach of collectors at particular localities. 
