OXYRHABDIUM 99 



Measurem.enfs of the type of Natrix dendrophiops negrosensis Taylor. 



mm. 



Length 730 



Snout to vent 526 



Vent to tip of tail 204 



Width of head 11 



Length of head 20 



Diameter of eye 5 



Variation. — The postoculars show a tendency to increase to 

 four; one specimen has the third, fourth, and fifth labials en- 

 tering the eye, and a second specimen shows four labials en- 

 tering on the right side. 



Remarks. — The following characteristics seem to warrant the 

 separation of this subspecies from typical Natrix dendrophiops. 

 There is a tendency to an increase in the number of postoculars 

 from 3 to 4; there is only a single preocular (specimens of N. 

 dendrophiops from northern Mindanao have 2 distinct preocu- 

 lars) ; there is an average of 10 more ventrals; there are con- 

 stantly 19 instead of 17 rows of scales; the eye is somewhat 

 smaller; and the loreal is lower. 



Genus OXYRHABDIUM Boulenger 



Stenognathus (non Chaud.) Dumeril and BiBRON, Erp. Gen. 7 (1854) 

 503; Jan, Arch. Zool. Anat. Phys. 2 (1862) 28. 



Rhabdosoma, part., Gunther, Cat. Col. Snakes Brit. Mus. (1858) 10. 



Geophis, part., Boettger, Ber. Senck. Nat. Ges. (1886) 106; Casto 

 DE Elera, Cat. Fauna Filipinas 1 (1895) 425. 



Oxijrhabdium Boulenger, Cat. Snakes Brit. Mus. 1 (1893) 302; 

 Griffin, Philip. Journ. Sci. § D 6 (1911) 258. 



"Maxillary teeth 30 to 35, small, equal ; mandibular teeth 

 equal. Head not distinct from neck; eye small, with vertically 

 subelliptic pupil ; nostril pierced between two small nasals ; a 

 pair of small internasals ; no prseocular ; loreal and prsef rental 

 entering the eye. Body cylindrical ; scales smooth, in 15 rows, 

 without apical pits ; ventrals rounded. Tail moderate, subcau- 

 dals in two rows. Hypapophyses developed throughout the ver- 

 tebral column." (Boulenger.) 



Key to the species of Oxyrhabdium Boulenger. 



a\ Eight upper labials, fifth and sixth entering eye; reddish brown above, 

 yellowish belov/. Young with yellow collar. 



0. modestnm (Dumeril and Bibron) (p. 100). 

 o'. Seven upper labials, fourth and fifth entering eye; olive green to darker. 



Y'oung black with dim yellowish rings on body -- - 



0. leporinum (Giinther) (p. 103). 



