48 
THE EACES OF THE MASCAEENES. 
Humerus. — The two collections contain together 18 specimens, among which again 
three types may be distinguished. 
a. The first type (Plate XXV. fig. A) is represented by six humeri with a slender 
and strongly bent shaft, and with a deep hollow behind the head of the humerus and 
between the tuberosities. The head is globular, or, in large specimens, ovoid, and 
nearly entirely raised above the level of the summit of the radial tuberosity. A groove 
indicating the course of vessels becomes distinct on the convex side of the distal third 
of the bone close to the radial edge, and perforates the lower end of the bone very 
near to the margin of the cartilage of the joint. The slight build of the humeri of 
this type would seem to indicate that they belong to the species with the thinner 
carapace, viz. T. triserrata. 
h. In the second type the hollow behind the head is absent or scarcely indicated. 
Otherwise it does not differ from the first, and is, perhaps, nothing but an individual 
variation. 
c. The third type (Plate XXV. fig. B), represented by eight specimens, has a much 
stouter and straighter shaft ; it is trihedral nearly in its whole length, a strong ridge 
generally running down from the tuberosities to the radial margin of the condyle. 
On account of its greater strength, this form of humerus may be associated with the 
heavier carapace of Testudo inepta. 
Measurements. 
T. triserrata. T. inepta. 
110.39947. No. 39946. No. 39942. No. 39944. No. 39943. 
millim. millim. millim. millim. millim. 
Length of humerus (measured in a straight line 
from summit of head to the middle of 
trochlea) 137 110 184 119 160 
Circumference of the narrowest part of shaft ... 55 47 83 63 88 
Largest diameter of head 28 24 46 29 39 
Shortest diameter of head 25 20 30 20 27 
Extreme breadth between condyles 45 38 76 43 58 
l/lna. — Two examples of ulna are preserved in the British Museum series : the 
smaller is that of an animal still growing; the larger (No. 39948) belongs to the left 
side and is 110 millims. long ; it has a comparatively narrow shaft, not more than 15 
millims. wide in its narrowest portion. The shaft is considerably twisted round its 
longitudinal axis, so much so that the transverse diameters of its proximal and distal 
dilatations stand nearly at right angles to each other. The olecranon is well developed. 
Badins. — Four specimens are preserved in the British Museum series, differing con- 
siderably from one another, but leaving it quite uncertain whether these differences 
are merely accidental and individual or specific. 
a. One radius of larger size (No. 39950) (Plate XVIII. fig. D) and another smaller 
