430 
APPENDIX. 
EB, 
second ; the fourth only half as long as the third ; and the 
fifth about half the length of the fourth toe. 
Genus TRACHYSAURUS. Gray. 
Pedes quatuor pentadactyli. 
Caput sub-scutatum, dentes in palato nulli. 
Truncus supra Squamis crassis elongatis subspinosis, infra hex- 
agonis raembranaceis imbricatis, tectus. 
Cauda brevis, depressa. 
This genus is at once distinguished from the former, and in-^ 
deed from the whole of the ScincidcB, by the large hard scales 
that cover the back of the body and head ; which are formed 
of distinct triangular long plates, rough on the outside, and 
covered with a membranaceous skin. The bony shields of 
the head pass gradually into the dorsal plates. The teeth 
short, thick, and conical; the palate toothless. The belly and 
lower surface of the tail are covered with large six-sided 
scales, like the other genera of the family. The head is 
rather large, triangular. The legs short, weak ; the toes 
very short, covered only with as many scales as there are 
joints ; the outer and innermost being about half as long 
as the three central toes, which are nearly of equal length 
claws short, conical, channelled beneath. The tail short, 
depressed. 
5. Trachysaurus rugosus, (n. s.) 
T. squamis dorsi rugosis, caudce subspinosis ; cauda bre^ 
vissima. 
The body nearly uniform, chestnut brown; the head de- 
pressed with the scales convex, and more nearly of an 
equal size than usual: those round the eyes and mouth 
large; the three anterior scales on the edge of the lower 
jaw larger than those which cover the lower surface of 
the head, body, and tail, which are uniform, distinct, 
large, and membranaceous: the scales of the back are 
