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Show 1896.] BATRACHIANS OF THE MALAY PENINSULA. 899 length of the hind foot; while in all the adult Singapore specimens examined the breadth across the gape is greater than the distance from angle of mouth to end of snout, and equal to or greater than the length of the bind foot, but in the young of the Singapore variety the gape is less than the hind foot. The interorbital space in the largest Penang specimen is equal to, in the six others less than, tbe upper eyelid, in some considerably less ; in the Singapore variety, in young specimens the interorbital space is slightly less than the upper eyelid, in fair-sized specimens equal to it, and in large specimens one half broader than the upper eyelid. Blanford mentions the Singapore frog as having a smaller eye; but if specimens of similar size of the two varieties are compared, it will be seen not to be noticeable. Tympanum distinct, slightly larger in the Singapore variety, but variable in size ; it is also variable in shape, when not circular, in the Singapore variety it has its greater diameter in a vertical position, in the Penang variety in a horizontal direction. In the Singapore variety a strong, prominent fold (well-developed in even quite small specimens) runs from behind the eye horizontally to over the tympanum, and then turns down at an obtuse angle and runs straight to the shoulder; in the Penang variety this fold is much less prominent, and instead of forming an obtuse angle forms a curve above the tympanum ; however, this character cannot divide the two forms, as in the British Museum specimens will be found with every gradation from the angular to tbe curved fold. Fingers moderate, first much longer than the second; toes broadly webbed, in the Singapore variety the web is more deeply emarginate than in the Penang variety, the terminal two phalanges of the fourth toe have only a narrow fringe of web along their sides. The tarsal fold is very variable in size, and often wanting. The fingers and toes have slightly though distinctly swollen tips, and the subarticular tubercles of fingers and toes are well developed; the inner metatarsal tubercle is elongate and blunt, there is no outer tubercle : in these characters there is no difference between the two varieties. The hind limb being carried forward along the body the tibio-tarsal articulation reaches beyond the eye, usually to the end of the snout: the Penang specimens have on the whole longer hind legs than those from Singapore when measured in this way. Skin smooth above. Hinder portion of upper eyelid tubercular. In young specimens there is a narrow glandular fold on each side of the back, and other, both round, and longitudinal, glands scattered over the skin of the upper surfaces; these glands gradually disappear with age, but seem more persistent in the Penang variety. Male without vocal sacs. Blanford distinguished the Singapore variety from Rana fusca (Blyth) by, 1st, a much broader head; 2nd, a smaller eye; 3rd, a larger tympanum; 4th, flatter muzzle; 5th, nostrils nearer together; 6th, web of the hind toes less developed. Although, as mentioned |