1901.] BATRACHIANS PROM ARABIA. 141 



outer border of the rostral, in a single shield resting on the 1st, 2nd, 

 and 3rd upper labials. Pive upper labials, the fourth and fifth the 

 largest, the first lying below and close to the nostril. A large 

 quadrangular postnasal lying above the 3rd, 4lh, and 5th labials 

 and below the anterior half of the ocular shield. Ocular plate 

 considerably longer than deep, partially divided about the middle 

 of the eye ; a large postoeular with three shields between 

 it and the hinder margin of the gape. A subocular, higher 

 than broad, lying between the postnasal and the shield below the 

 postoeular. Three lower labials, the first only in contact with the 

 mental ; the last very large and elongated from above downwards, 

 separated from its fellow of the opposite side by seven scales which 

 are shut off from the posterior end of the chin-shield and from the 

 first and second labials by seven other shields and scales, one or 

 two of the shields being in contact with all the lower labials. 

 Mental very elongate and ribbon-shaped, reaching as far back as 

 the posterior border of the second labial. 161 annuli on the body, 

 18 on the tail. About 55 scales round the body, including the 

 irregular scales of the vertebral and ventral lines, in the former of 

 which there are about 7 and in the latter 3; each annulus containing 

 about 45 quadrangular segments. 



Salmon-coloured in life, the majority of the segments of the 

 annuli being generally partially or wholly marked by a dark 

 brown spot, absent, however, from the lower half of the sides and 

 ventral aspect ; head-plates yellowish. 



A single specimen, from the Abian country, measuring 144 

 millimetres. 



This species is the first of the Emphyodont group of Amphis- 

 bsenidse which has been recorded from the Asiatic Continent, but 

 Pachy calamus is found in Socotra. 



Three species of Agamodon are known, viz., A. anguliceps Peters \ 

 the type of the genus, A. compi'essus Mocquard ^, and A. arabicus 

 Anders. The first was described from a specimen obtained at 

 Barava, and the second also from Somaliland. They constitute 

 three well-defined species distinguished from one another by 

 the number of annuli round the body. In the first they do 

 not exceed 133. In A. compressus there are as many as 147, 

 and in A. arabicus there are over 160. A. ay^hicus has a greater 

 number of upper labials than in the African forms, but it is 

 quite possible that with further materials the supposed dis- 

 tinction will vanish. It also differs from the other species in 

 the way in which the second lower labial is broadly excluded from 

 the mental. 



A. arabicus has the compressed form of A. compressus, from 

 which it is at once distinguished by the shape of its frouto-parietal 

 in addition to the other characters here enumerated. 



1 Peters, Sitz. Ak. Wiss. Berl. 1882, p. 579, pi. x. 



2 Mocquard, Mem. Cent. Soc. Philom. 1888, p. 121*, pi. xi. figs. 2, 2 a to 2 c, 



