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Show 36 ZOOLOGY OF TilE VOYAGE OF TilE BEAGLE. BoanonocmTES GnAYII. Milti. PLATE XVII.-Fig. 2. .Dentibus palatinis in fasciculis subcontiguis paulo obliquis. pone na1·es posteriores positis; palmis non tuberculatis. Habitat, Valdivia. This species considerably resembles· the fo~mer in mo~t of .its. ch~racters. 'J'he palatine teeth, however, form at once a certam and tangtble dtstmchon, and there are some minor points in which they differ, sufficient at a glance to determine them. The head in the present animal is broader than it is long; in the former the breadth is only equal to its length. The palms are in this species without conspicuous tubercles ; in the other there are two, although very small. In colour it differs much from the former. The general colour is a rich fuscous brown, rather paler beneath; the flanks, the throat and belly, and the whole of the thighs and legs, with various white markings, those of the throat and belly being the smallest. This species was found in the forest, in Valdivia. GENUs-PLEURODEMA. Tscltudi. I have thought it right to follow Tschudi in separating from the genus Cystignatltus of Wagler, such species as have large and conspicuous lumbar glands, particularly as they all agree in possessing a much more bufonine aspect than the others. The discovery of three new species, all agreeing in these characters with Pleurodema Bibronii of Tschudi, increases the importance of the grounds upon which this separation is made. PLEURODEMA DARWINII. Milti. PLATE XVII.-FrG. 3. Dentibus palatinis paucis, minimis; lingua subcordatd, vix emarginata; glandulis lumbo1'Um magnis, rotundis, convexis; digitis posticis ad basin tantum membmnd connexis; dorso sparstm tuberculato-glanduloso; supra pallide vit·escens, maculis fusco-olivaceis. Habitat, Maldonado. REPTILES. 37 DEscn~PTION.-Hcad triangular, rather broader than long. Muzzle rounded. Eyes slightly promment. Tongue somewhat heart-shaped, scarcely emarginated behind. Palatine teeth ver few, and with difficulty perceptible, placed in two small groups between the posterior narc:. Body thick and b.road, with numero1~s glandular tubercles scattered over the surface, principally on the antenor parts, and assummg somewhat of a longitudinal arrangement. Lumbar glands large, round, and prominent. Legs robust and short. Toes of the fore feet wholly separate, with a small tubercle under each joint, and two larger ones at the hinder part of the palm. Hinder toes, with a rudimentary membrane at the base, a small tubercle under each joint; the first and second toes very short. A conical tubercle at the inner, and another at the outer side of the metatarsus. CoLOun.-The upper surface is beautifully marbled with dark olive or black, on a light-green ground; some of the markings assume somewhat of an oeellated form, and approach to a symmetrical arrangement. The lumbar glands are more strongly coloured than the other parts, the centre being black, and nearly surrounded by a bright line of very light green, or nearly white. The thighs are numerously banded with the prevailing colours, and a tinge of orange or red. Beneath pale; in some specimens blackish under the chin. The aspect of this species is remarkably bufonine ; and this character is increased by the numerous glandular tubercles on the surface of the body, anrl pores about the parotid region. It is, doubtless, similar in its habits to many of the toads. DIMENSIONS. In. Lin. Length of the bend and body.................. 1 4 of the anterior extremities . . . . . . . . . . . . 0 8 of the posterior extremities .. .. . .. .. 7 It was repeatedly found by Mr. Darwin at Maldonado, near the mouth of the river La Plata. PLEURODEMA ELEGANS. Mi/ti. PLAIE XVII.-FIG. 4. Dentibus palatinis prominentibus, in fasciculis binis ovatis obliq1tis dispositis; lingua rotunda integra; glandulis lumborum ovalibus, valde ~onvexis; di.gitis posticis ltaud palmatis ; dorso tuberculato-glanduloso, fusco, mgro obscure maculato, fascid longitudinali pallidd. Habitat, Valparaiso, Valdivia, and Archipe1ago of Chiloe. DESCRIPTION.-Ilead semi-elliptic, as broad as long. Muzzle rounded. Eyes very slightly prominent. Tongue large, round, entire, very thick. Palatine teeth prominent, disposed .in two |