628 JOURNAL, BOMBAY NATURAL HISTORY SOCIETY, Vol XX. 



genus by attention to the following points: — (1) Lachesis trigono- 

 cephahis has no enlarged plate-like shields on the head, a pit in 

 the side of the face, strongly keeled scales, and a vertical pupil ; 

 (2) Oh/rysopelm ornata has the ventral shields keeled on each 

 side ; (3) Gerardia prevostiana has only 5 shields touching the 

 rostral. 



It remains now to separate condanarus from the other three 

 species of Psammophis, and here the nasal shields will suffice.* In 

 condanarus there is either a single nasal shield partially divided 

 by a suture running from the nostril to the first labial as shown 

 in Diagram I, figure B, or another suture above the nostril may 

 completely divide the shield into two. In the other three species 

 the shield is not only completely divided vertically into two parts, 

 but the posterior part is further subdivided by a horizontal suture 

 as shown in our Diagram (figure E). 



To sum up the points to look for, and in the order here given are — 



(1) Costals 17 — 17—13. 



(2) Large plate like head shields. 



(3) Rounded ventrals. 



(4) Rostral touching 6 shields (see Fig. D of diagram). 



(5) Posterior nasal not divided into two parts. 



1 1 mints. — I have very rarely met with this snake myself in its 

 natural haunts, but from enquiries made from those who have 

 brought me specimens it appears to frequent grass land, and rather 

 open jungle. In Fyzabad it came occasionally into the Canton- 

 ment, but was more often encountered in the little patches of 

 tamarisk (jhow) outside Cantonment limits. Here it was fre- 

 quently met with in the branches of the tamarisk shrubs showing 

 a decided arboreal tendency. On one occasion it came into a 

 house in the Cantonment. In Almora it is found usually in the 

 wooded patches in and close at hand. Mr. P. W. MacKinnon, 

 who gave me specimens, told me that it is common about 



* The undivided condition of the anal will proclaim the identity of leithi. In 

 schokari the supralabials are usually 9 with the .*<th and Gth touching the eye, and 

 the frontal touches 8 shields. In longifrons the frontal touches 6 shields and 

 tin- supralabials are usually 8, rarely !>, with the 4th and 5th (rarely 5th and fith) 

 touching- the eye. 



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