178 OPHIDIA. 



FAMILY OF mOnT-TAlL^—lVRTRICW^. 



Body cylindrical; with a depressed, rounded head not distinct from neck ; 

 tail extremely short, conical, with its extremity smooth. Rudiments of hind 

 limbs are hidden in a small groove on each side of the vent. The body is 

 covered with rounded, polished, imbricate scales of moderate size, those in 

 the ventral series being but little larger than the rest. Only one pair of 

 frontals ; six upper labials. Eye small. Cleft of the mouth of moderate 

 width ; teeth of the jaws in small number, rather stout, subequal in size ; 

 palatine teeth present. A longitudinal fold at the chin. 



The species occurring in the East Indies belong to one genus only. 



CYLINDROPHIS, TFa(/ler. 



Nostrils in a large undivided plate which forms a suture with the other 

 nasal behind the rostral. Occipitals small. Eye small, with round pupil, 

 surrounded by a supraorbital, a postocular, two labials, and the frontal ; 

 only one pair of frontals. No intermaxillary teeth. 



Two of the three species known are inhabitants of British India, the thii'd (C. melanonotus) 

 being, apparently, peculiar to the island of Timor. They are extremely similar to one 

 another, differing merely in coloration and in the form of the head, whilst the arrangement 

 of the shields of the head is the same. 



The head is depressed, scarcely distinct from the neck, with the cleft of the mouth ex- 

 tending backwards behind the occipitals. Eye small, more or less directed upwards ; trunk 

 cylindrical; tail extremely short, conical, terminating in a horny, conical, smooth scale. 

 Rostral shield low, not extending far backwards. The two nasals are rather large, forming 

 together a suture behind the rostral; their anterior outer portion is pierced by the nosti-il. 

 Only one pair- of large frontals, entering the orbit ; a vertical ; a supraorbital, which is as large 

 as, or even larger than, the small occipitals. Six upper labials, the third and fourth of which 

 form the lower part of the orbit ; a very distinct postocular, followed by a very large temporal, 

 behind which are situated two pairs of scale-like temporals. Mental shield small, triangular : 

 five or six lower labials ; the first pair form a suture together behind the mental shield. One 

 pair of chin-shields, separated by a deep groove from each other ; three pairs of labials are 

 in contact with the chin-shields. Scales smooth, polished, rounded, without apical groove, 

 in nineteen or twenty-one series. The ventral shields scarcely differ in size from the other 



