3. SILYBURA. 145 
B. Tail with a flat disk of strongly keeled scales; 203-230 
ventrals ; diameter of body 34 to 40 times in total length. 
11. broughami, p. 152. 
II. 17 scales round the middle of the body. 
A. Rostral entirely separating the nasals, 
141-166 ventrals; diameter of body 22 to 
31 times in total length ; eye not half 
length of ocular ................ 1. melanogaster, p. 146. 
161-180 ventrals ; diameter of body 30 
to 38 times in total length ; eye half 
length of ocular ..... We wims sicolnn 2. pulneyensis, p. 147. 
B. Nasals in contact behind the rostral. 
1, Eye not half the length of the ocular shield. 
a. Portion of rostral seen from above as long as its distance 
from the frontal, or shorter ; snout obtuse. 
a. Tail round or slightly compressed ; upper caudal scales 
distinctly keeled; terminal scute without distinct 
points ; 151-180 ventrals ; diameter of body 25 to 33 
times in the total length. 4. petersii, p. 148. 
B. Tail round or slightly compressed ; upper caudal scales 
smooth or faintly keeled ; terminal scute very small 
and bicuspid. 
152-173 ventrals ; diameter of body 27 
to 40 times in total length .......- 5. maculata, p. 149. 
174-188 ventrals ; diameter of body 32 
to 38 times in total length ........ 6. liura, p. 149. 
y. Tail with a flat disk of strongly keeled scales; 165- 
172 ventrals; diameter of body 30 to 33 times in total 
Baas c's Sexe n.0 6 0%, 6.0 16. rubrolineata, p. 155. 
b. Portion of rostral visible from above longer than its distance 
from the frontal ; upper caudal scales strongly keeled. 
a. Rostral not more than one third the length of the shielded 
part of head. 
193-234 ventrals; diameter of body 30 
to 46 times in total length ; eye hardly 
one third length of ocular.......... 7. ocellata, p. 150. 
184-195 ventrals ; diameter of body 30 
to 35 times in total length; eye more 
than one third length of ocular .... 9. nitida, p. 151. 
144-172 ventrals ; diameter of body 25 
to 32 times in total length ........ 14, ellioti, p. 154. 
B. Rostral compressed, keeled above, at least two fifths the 
length of the shielded part of head ; snout acutely pointed. 
"156-168 ventrals ; diameter of body 26 
to 32 times in total length; caudal 
Seeramek Quite flat...........-.sseees 10. dindigalensis, p.152. 
L 
