328 



COLITBRID^. 



Fie. 22. 



Skull of Boodon olivaccus. 



Synopsis of the Species. 

 I. Subcaudals in two rows. 



A, Prseocular not extending to upper surface of head; usually, 



three labials entering the eye. 



1. Scales in 21 or 23 rows : rostral about once and a half as 



broad as deep. 



Prontal as long as parietals 1. lemniscaius, p. 329. 



Frontal shorter than parietals 2. geometricvs, p. 32!J. 



2. Scales in 23 or 25 rows ; rostral nearly twice as broad as 



deep 3. infernalis, p. 330. 



B. Pra30cular extending to upper surface of head, and often in 



contact with the frontal. 



1. Scales in 23 rows. 



Subcaudals 47-61 4. virgatus, p. 331. 



Subcaudals 72 , 5. guttatus, p. 331 . 



