118 



colubrid.t:. 



B. Pupil vertically elliptic ; scales 

 smooth or feebly lieeled ; ventrals 

 178-265; subcaudals 50-110*. 



Some of the anterior teeth enlarged, fang- 

 like, separated from the rest by an inter- 



f space ; scales in 17 or 19 rows Lycodon, p. 131. 



Maxillary teeth short, increasing in size 

 posteriorly ; scales in 13 or 15 rows .... 



C. Pupil round ; head distinct from 



neck; scales smooth or feebly keeled 

 (rarely strongly keeled) ; ventrals 

 often keeled or angulate laterally, 

 160-285 ; subcaudals 50-165. 

 1. Scales in 14 or 16 rows . . , r. . . . Zaocys, p. 135. 



Dbyocalamus, p. 134. 



* Unless otherwise stated in the generic diagnoses, the upper Lead-shields 

 are understood to be normal, viz., to consist of a rostral, a pair of internasals, 

 a pair of prafrontals, a frontal, a pair of parietals, and, on each side, a' 

 su])raocular, one or two nasals, a loreal, one or more pra;- and postoculars, 

 temporals, and several labials. 



Fig. 39. — Three views of head of Zamcnis ventrimacidaius, to explain the 

 terminology of the head-shields. 



(\<. Chin-shields (nnterior). 



cs'. Chin-shields (posterior). 



/. Frontal. 



in. Internasal. 



I. Loreal. 



la. Upper labials, 



la' . Lower labials, 



Symphysial. f^ho. Siiboculnr. 



II. Nasal. 



/). Parietal. 

 pf, Pra'frontal. 

 pro. Prsvocular. 

 pio. Postocular. 



r. Rostral. 



I. Supraocular. 



/ . Temporals (first row), 



f . Temporals (second row). 



('. First ventral. 



