187 
which bordor the cleft of the mouth. Lower labials 11. Scales in 17 
rows, keeled and covered with very narrow stripes. 
25. Lepidognathus rugosus n. sp. (plate XVI, fig. 1, 2, 3, 4 and 5). 
Sumatra: Kaju tanam, 1 spec. 
The only specimen of this species has the upper part of the head 
and the back of an olive-colour, whilst the margins of the scales are 
whitish; the underparts of the head, the anterior upper-labials, the 
ventrals, the outer row of scales and the lower half of the penulti- 
mate row are yellow. 
. A fold behind the nostril runs straight through the nasal, thus as 
it were dividing it into two parts. The nasals rest on the two anterior 
and a part of the third upper-labial, they are separated by two al. 
most crescent-shaped anterior frontals, which form together a triangle 
with a rounded top. The three-sided loreal rests on the anterior part 
of the fifth, on the fourth and on the posterior part of the third 
upper-labial; the pretty large praeocular on the posterior part of the 
fifth upper-labial. The small scales below the orbit, three in number, 
rest on the sixth , seventh , eighth and ninth upper-labials. The tenth 
upper-labial touches the first of the temporals, whilst the eleventh 
and the twelfth upper-labials, greatly inferior in height to the ten 
preceding ones, are in contact with the posterior temporals. There is 
a longitudinal groove between the ten anterior upper-labials and the 
shields above them. The third, fourth, fifth, sixth, seventh, eighth, 
ninth and tenth upper-labial are resting on a row of small trigonal 
scales which border the cleft of the mouth. 
The five-sided vertical is as broad as high, and is bordered on both 
sides by the supraciliaries , that of the left side being divided into 
two shields. The postocular closes the ring round the orbit formed by 
the supraciliaries, the praeocular and the three small shields below 
the eye. 
The mental shield is rather narrow; the first pair of lower labials in 
contact behind the mental. Two small scales between the second pair of 
chin-shields. Our specimen has 170 ventrals, a divided anal and 95 pairs 
of subcaudals. The ventrals and subcaudals are smooth, the scales on 
the back, the flanks and the tail with many smaU longitudinal stripes, 
which give the surface a rough appearance. There is a strong den- 
ticulated keel on each of the scales. 
