382 COLUBllID.E. 



y. Eight upper labials 19, elejantissiimts, 



[p. 402. 



3. Scales in 21 or 23 rows ; two labials enter the eye. 



a. One proeocular (rarely divided), with a subocular below it ; 

 scales smooth. 



Nine upper labials ; subcaudals not more 



than lUO 20. Jljridentus, p. 402. 



Nine upper labials ; subcaudals more than 



100 21. fjmciUs, p. 404. 



Eight upper labials ; subcaudals less than 



100 22. fasclolatus, p. 404. 



h. Two pra3oculars in addition to the subocular ; scales with 

 an obtuse or faint keel 23. raverr/ieri, p. 405. 



4. Scales in 23 or 25 rows, usually a single labial enters the 



eye. 



a. Two pra30culars in addition to the subocular. 



Scales obtusely or faintly keeled ; ventrals 



197-216 ; subcaudals 79-101 24. nummifer, p. 407. 



Scales perfectly smooth ; ventrals 219-228 ; 



subcaudals 107-119 25. socotrtv., p. 408. 



h. One pra30cular, with a subocular below it ; ventrals 214- 

 232 ; subcaudals 87-104 .... 20. algirm, p. 408. 



5. Scales in 25 to 29 rows ; eye usually separated from the 



labials by suboculars 27. lilppocrepis, p. 409. 



6. Scales in 31 rows ; two labials entering the eye, 



2^. dorri, p. 410. 



II. Pra}frontaLs broken up into three or more shields ; ej^e separated 

 from the labials by suboculars ; anal entire. 



A. Scales in 25 to 33 rows ; 10 to 13 upper labials. 



llostral as deep as broad or a little broader 



than deep 29, cUadema, p. 411. 



llostral much deeper than broad, wedged in 



far between the interuasals 30. arenavius, p. 413. 



B. Scales in 41 to 43 rows; 14 or 15 upper labials. 



31, microhins, ]). 413. 



As has been done for the genus Tropidonotns, a table is appended 

 showing the numbers of scales and shields in the ditferent species, 

 with the object of facilitatii g the identification of specimens : — 



