TESTUDO SEMISERRATA. 
and irregular from their being strongly cut by numerous polygonal grooves. 
Nuchal plate triangular; the first and fourth dorsal plates pentagonal, the 
second, third and fifth hexagonal, but the form of the last is very different 
from the other two ; the caudal plate pentagonal, its apex slightly incurved ; 
the first costal plate rather irregular in shape and generally octagonal, some 
of the sides very short and indistinct, second and third plates hexagonal, the 
fourth pentagonal. The anterior and posterior marginal plates somewhat 
triangular, the intermediate ones subquadrangular ; those of the first descrip- 
tion, particularly the four last of each side, with prolonged points, each of 
which are inclined obliquely backwards. The sternum is slightly convex, and 
its anterior and posterior extremities bifurcate ; the gular plates are some- 
what diamond-shaped ; the humeral ones large and quadrangular ; the 
pectoral ones narrow where they are in contact with each other, and from 
thence gradually increase in breadth to their outer margins which are two- 
sided ; the abdominal plates are large and square ; the femoral ones broader 
at their outer than their inner edges, and the caudal ones are quadrangular, 
the outer and hinder angle being slightly prolonged and rounded at the tip. 
Upper surface of head closely covered with small flat and irregular-shaped 
scales, those immediately over eyes smallest ; upper mandible cut by several 
vertical furrows and strongly hooked at the point, its cutting edge waved and 
finely dentated ; lower mandible pointed, the point ascending. Neck closely 
coated with minute granular scales ; fore-legs covered with subovate scales, 
among which, above the claws, are interspersed a few large tubercular ones, 
the form of one of which, the largest, is nearly that of a shell of the genus 
Crepiclula ; hind-legs coated with small delicate scales, and, internally, each has 
at its base a strong conical tubercle ; claws of fore-feet rather short and nearly 
straight, those of the hinder feet much longer and slightly curved. Tail short 
and conical, with a small, prominent, conical tubercle on each side of its base. 
The length of the largest shell we obtained was nearly five inches, and as 
specimens of the same size, as well as of others much smaller, occurred in 
great abundance, we had reason to consider the largest as examples of full- 
grown individuals. 
The districts between Latakoo and the Tropic of Capricorn abound in individuals of this 
species. 
The shape of the nuchal plate and the form of the tubercular scales upon the fore-legs, are 
characters by which Testudo semiserrata is readily to be distinguished from T. geometrica, to 
which it closely approximates. For the appearances of these parts in both species, see Plate, 
a, a Testudo semiserrata ; b b Testudo geometrica. 
