g§ SNAKES OF THE PHILIPPINE ISLANDS 



Descri'ption of species. — (From No. 163, Bureau of Science col- 

 lection; collected at Iwahig, Palawan, by C. M. Weber.) Head 

 rather elongate, distinct from neck; rostral much broader than 

 high, visible from above; internasals longer than wide, about 

 as long as prefrontals, the suture between them nearly equal to 

 that between prefrontals ; frontal about one and two-third times 

 as long as broad, shorter than supraoculars, as long as its dis- 

 tance to end of snout, much shorter than parietals ; latter much 

 longer than broad, in contact with 1 postocular and 2 (3 on left 

 side) temporals; nasal large, divided or nearly so; loreal about 

 as deep as long ; 1 preocular, higher than wide ; eye large ; 3 

 postoculars ; 9 upper labials, fourth, fifth, and sixth entering eye, 

 seventh and eighth largest; mental much broader than deep; 

 11 lower labials (the first anterior on left side broken) ; fii'st 

 pair of chin shields shorter and broader than second pair, touch- 

 ing first 6 labials; second pair of chin shields touching labials 

 entire length ; scales strongly keeled, in 19 rows, outer row 

 largest; ventrals, 152; anal divided; subcaudals, 69. 



Color. — Above grayish brown, the skin between the scales 

 rather reddish brown ; a lateral row of small brownish yellow 

 spots from head to tail ; labials with yellowish spots ; chin and 

 belly immaculate, outer edges of ventrals grayish. 



Measurem-ents of Natrix chrysarga (Sclilegcl) . 



Total length 825 



Snout to vent 625 



Tail 200 



Width of head 18 



Length of head 30 



Variation. — Not a great deal of variation obtains in the speci- 

 mens examined. The counts of ventral scales vary within the 

 limits of 150 and 160; of subcaudals, between 80 and 90. Bou- 

 lenger gives 143 to 175 for the ventral range ; 60 to 93 for the 

 subcaudal range. 



The young are very distinctly marked. The head is dark gray- 

 ish brown, with two black-edged, white, parietal spots ; there is a 

 yellow bar on the side of the head in front of the eye, edged 

 anteriorly with black; the labials entering the eye are yellow, 

 edged with black; a vertical bar is present immediately behind 

 the eye ; the neck is blackish with a broad V-shaped, yellow mark 

 crossing it from the angles of the mouth. The body is gray- 

 bro\vn ; the five median scale rows are slightly darker than the 

 adjoining rows, and are traversed by numerous, regular black 



