113. Groruis. 315 
II. Two pairs of chin-shields, 
A. Maxillary bone extending in front much beyond the palatines ; 
scales perfectly smooth. 
A supraocular ; third upper labial enter- 
ing the eye; scales in 15 rows; ven- 
Grabs Uy phe, ee ee re eae isis 2. semidoliatus, p. 316. 
No supraocular; third ‘and fourth upper 
labials entering the eye; scales in 17 
rows: -ventrals 1g5-144 ae. te 3. rhodogaster, p. 317. 
B. Maxillary bone extending in front a little beyond the pala- 
tines. 
Scales in 15 rows, perfectly smooth; ven- 
tree ss WO, -eeee ces igen a aaehye Se: 4, dugesti, p. 317. 
Scales in 15 rows, striated and keeled ; 
premiera WO A heparan eae tesla, oi 5. oaks 5. sallei, p. 318. 
Scales in 17 rows, striated and keeled on 
the posterior half of the body; ventrals 
Rey eed eae Si onsica auc; Yw ate ea din ake eas 6. chalybeus, p. 318. 
C. Maxillary bone not extending in front beyond the palatines. 
1. Upper portion of rostral uot measuring more than one 
third its distance from the frontal; scales in 15 rows. 
Scales perfectly smooth on the anterior 
part of the body, striated and very feebly 
keeled further Wacke. <i. 2% 7. bac ee 7. hoffmanni, p. 319. 
Scales very distinctly striated and keeled, 
the kee] rather strong on the posterior [p. 320. 
part of the body and on the tail ...... 8. dolichocephalus, 
2. Upper portion of rostral measuring at least two thirds its 
distance from the frontal; scales all smooth, or those at 
the base of the tail very faintly keeled. 
a. Scales in 15 rows. 
A supraocular; prefrontals as broad as 
iFeug=? OR ale. ias a °cuaweRPES Grek ae ae eee 9. petersit, p. 321. 
A supraocular; prefrontals longer than 
IDEOAGL tr crt pee he pettiness ae 10. champions, p. 321. 
No supracculane ysis oe ae 25) Stew. « « 11. yodmani, p. 322. 
b. Scales in 17 rows. 
First lower labial in contact with its fellow 
behind the symphysial.............-. 12. dubius, p. 322. 
Symphysial in contact with the anterior 
One Oat epee ia ea oe en 13. rostralis, p. 323. 
