Description.—Head triangular, rather broader than long. Muzzle rounded. Eyes slightly prominent. Tongue somewhat heart-shaped, scarcely emarginated behind. Palatine teeth very few, and with difficulty perceptible, placed in two small groups between the posterior nares. Body thick and broad, with numerous glandular tubercles scattered over the surface, principally on the anterior parts, and assuming 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.

Colour.—The upper surface is beautifully marbled with dark olive or black, on a light-green ground; some of the markings assume somewhat of an ocellated 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, and pores about the parotid region. It is, doubtless, similar in its habits to many of the toads.

It was repeatedly found by Mr. Darwin at Maldonado, near the mouth of the river La Plata.

Pleurodema elegans. Mihi.

Dentibus palatinis prominentibus, in fasciculis binis ovatis obliquis dispositis; lingua rotunda integrâ; glandulis lumborum ovalibus, valdè convexis; digitis posticis haud palmatis; dorso tuberculato-glanduloso, fusco, nigro obscurè maculato, fasciâ longitudinali pallidâ.

Habitat, Valparaiso, Valdivia, and Archipelago of Chiloe.

Description.—Head semi-elliptic, as broad as long. Muzzle rounded. Eyes very slightly prominent. Tongue large, round, entire, very thick. Palatine teeth prominent, disposed in two oval groups, extending obliquely backwards and inwards, but separated by a considerable interval. Body somewhat depressed and elongated, with many prominent glandular tubercles, and with pores about the parotid region. Lumbar glands of moderate size, of an elongated oval form, and very convex. Legs rather slender, the anterior feet with the third toe considerably the longest; a small tubercle under each joint of all the toes, and several small inconspicuous ones on the palm; hinder legs rather elongated, the toes long, particularly the fourth, the first very short; a small tubercle under each joint; the inner metatarsal tubercle prominent, the outer one inconsiderable.

Colour.—The markings of this species are very elegant and striking. The ground colour of the upper parts is a rich brown, with darker cloudings and marks; a light yellowish longitudinal line running all the length from the nose to the extremity of the body, a very irregular fascia on each side of the same colour enclosing a brown oblong spot on the upper lip, another just behind the tympanum, and two others on the sides; there is also a brown fascia from the extremity of the nose to each eye; the lumbar glands are black and yellow, distinctly marked. The limbs are obscurely banded with brown and pale yellowish. The colours in some specimens are more obscure than in that figured, and they appear to lose their clearness with age.

The following are the colours of the brighter individuals according to the observations of Mr. Darwin:—“Yellowish and broccoli-brown, with darker brown marks; broad medial dorsal line, pale gallstone yellow; lumbar glands saffron yellow and jet black.” Another specimen was “ash-grey with blackish brown marks.”

The general habit of this species is much more in accordance with its relation to the Ranidæ than that of the other species of the genus. Its general form is more elongated and depressed, and the limbs, particularly the hinder ones, are longer in proportion to the body. It is certainly very near Pl. Bibronii of Tschudi, but still undoubtedly distinct.

Dentibus palatinis prominentibus, in fasciculis binis ovalibus, obliquis, dispositis; lingua subcordiformi, subemarginata; glandulis lumborum maximis, ellipticis, planis; digitis posticis dimidio ferè palmatis, marginatis; dorso glandulis parvis instructo,fusco-griseo maculis, nigris, lineâ longitudinali pallidâ.

Habitat, Port Desire, Patagonia.

Description.—Head short. Muzzle rounded. Eyes prominent. Tongue thick, slightly heart-shaped, scarcely notched on the posterior margin. Palatine teeth prominent, in two oval groups, converging backwards. Tympanum rather small, perfectly round, conspicuous. Parotid glands distinct. Body thick and broad, with small glandular tubercles dispersed over the surface, particularly at the anterior part. Lumbar glands extremely large, elliptic-ovate, flat. Legs of moderate length, rather robust. Anterior toes separated, excepting at the base; a small tubercle under each joint, and several very small ones on the palm; hinder toes united to about half their length, and bordered on each side to the extremity; metatarsal tubercles prominent; soles of the hinder feet with many minute tubercles.

Colour.—The upper surface of this species is of a brownish grey colour, sometimes greenish brown or dark olive, and with numerous irregular spots of dark-brown or black. Thighs and legs with fasciæ of the same colour. Beneath yellowish white; in some with numerous blackish dots under the throat.

Found by Mr. Darwin at Port Desire, in Patagonia, and high up the river Santa Cruz—“probably,” says Mr. Darwin, “the most southern limit for this family.”

Genus—LEIUPERUS. Bibr.
Leiuperus salarius. Mihi.

Suprà nigricans, lumbis maculis 3 vel 4 nigris, albo-marginatis.

Description.—The head is short, the opening of the mouth small, the tongue rather thick, very slightly emarginate behind, and with the posterior margin free. The eyes small; the tympanum not very conspicuous; there is a trace of a parotid gland on each side of the neck. The body is rather thick, and the limbs proportionally short. The hinder toes are only connected at the base by a rudimentary membrane, the first four gradually increasing in length, and placed along the side of the matatarsus, one beyond the other; the fifth on the same line as the fourth, but not more than half its length. The metatarsal tubercle is rather prominent, and there are small subarticular tubercles on the toes of all the feet.

Colour.—The colour of the upper parts is brownish black. On each side near the thigh are three or four perfectly round black spots, each surrounded with a white line. The under parts whitish.

Of this second species of a rare and remarkable genus, one specimen only exists in Mr. Darwin’s collection. It is only the third known instance, in the family of the Ranidæ, of the absence of palatine teeth; the others being Oxyglossus Lima of Tschudi, and Leiuperus marmoratus of Bibron. The present genus must be considered as nearly approaching the family of the Bufonidæ in the absence of palatine and the extreme minuteness of the maxillary teeth, in the extremely small gape of the mouth, the thick form of the body, the shortness of the limbs, and the existence of rudimentary parotid glands. I have not had an opportunity of comparing this specimen with those on which Bibron founded the genus, but I cannot doubt the specific distinction between them.

It was found by Mr. Darwin at Port Desire, and its habitat is very remarkable. “It is bred in and inhabits water far too salt to drink.”

Genus—PYXICEPHALUS. Bibr.
Pyxicephalus Americanus. Bibr.

Lingua cordiformi; dentibus palatinis in lineâ transversâ interruptâ, inter nares posteriores positis; tympano celato; dorso mammillato.

This curious species has, I believe, only once before been found. A single specimen exists in the French Museum, which was brought from Buenos Ayres by Mons. d’Orbigny, and which formed the subject of Mons. Bibron’s description. Mr. Darwin’s specimen was taken on the open plains at Monte Video.

Of the three species of this remarkable genus at present known, two are inhabitants of Africa, from whence they were brought by Delalande. As neither of them has as yet been figured, it was thought desirable that the present opportunity should be taken to exhibit some of the generic characters, and especially the hard horny spur on the hinder foot.

This genus is one of those bufonine forms of the Ranidæ which irresistibly lead us to doubt the correctness of the present received arrangement of the anourous Amphibia.

Genus—ALSODES. Bell..

Caput convexum. Lingua anticè acutè-producta, posticè rotundata, et libera. Dentes palatini inter nares posteriores. Tympanum celatum. Aperturæ Eustachianæ haud conspicuæ. Digiti anteriores ad basin tantùm—posteriores usque ad phalangem tertium membranâ connexi.

A genus of the Raniform group, nearly allied, as Mons. Bibron observes, to Scaphiopus, by the structure of the hands, which, although without any projecting rudimentary thumb, has a small process under the skin, along the extreme margin of the first finger. In common with the genus Bombinator, it has the opening of the Eustachian tubes so small as scarcely to be detected.

Alsodes Monticola. Mihi.

Description.—Head semi-elliptical, somewhat convex, with the muzzle nearly perpendicular; vertex smooth. Eyes of moderate size. Nostrils very small, opening upwards. Tongue broad and rounded behind, narrowing to a point at the apex, detached at the posterior part. Palatine teeth in two small approximate patches, between the posterior nostrils. Openings of the Eustachian tubes scarcely visible. Extremities of moderate length. The fore feet, with four rather short toes, connected at the base by a short membrane; the inner toe broad, and with a slight projection under the skin, along its inner margin; hinder toes connected as far as the joint of the second and third phalanges.

The colour of the only specimen in the collection has become totally changed into a smoky brown by the spirit, but the following is Mr. Darwin’s description of it when living: “On the centre of the back a strong tinge of grass-green, shading on the sides into a yellowish brown; iris coppery.”

Mr. Darwin found this species “in the island of Inchy, archipelago of Chonos, north part of Cape Tres Montes, from the same great height as Bufo Chilensis (from 500 to 2500 feet elevation) under a stone.”

Genus—LITORIA. Bibr.
Litoria glandulosa. Mihi.

Femoribus posticè glandulosis; digitis posticis brevitèr palmatis.

This species agrees in many respects with Litoria Americana of Bibron. It differs, however, in the toes being much less palmate, at least according to the generic character given by that excellent naturalist, and in the existence of numerous thick glands on the posterior part of the thighs. The very slight degree to which the extremities of the toes are dilated in the other species of this genus, and which would at first sight lead to their allocation amongst the Raniform rather than the Hyliform group, is in the present species even more strongly exhibited; and it can scarcely be said that any dilatation exists at all.

The colours in the only specimen brought by Mr. Darwin are much obscured. The upper parts are apparently of an uniform brown, the under parts whitish, dotted with brown.

It was taken by Mr. Darwin at Concepcion, in Chile.

Lingua suborbicularis, posticè libera. Dentes palatini in fasciculis binis obliquis inter nares posteriores dispositi. Tympanum distinctum, parvum, rotundum. Digiti depressi, ad apicem paullò dilatati, truncati. Anteriores ad basin tantùm—posteriores paulò plus palmati.

This genus, which considerably resembles Hylodes, is nevertheless sufficiently distinct from it, in the distribution of the palatine teeth, in the form of the dilatations of the toes, in the presence of a small palmar membrane, and some other points. One of the most remarkable of its characters is the form of the dilatation at the extremity of the toes; it is very small, transverse, truncated, and even a little emarginate; in this respect it must be considered as constituting a very near approach to the family of the Ranidæ. We are unfortunately without any information as to the habits of the only known species which could throw any light upon its relations; but it is very clear that the dilatations of the toes are not such as to constitute it a true tree-frog, nor, on the other hand, are the connecting membranes of sufficient extent to give it the typical character of the swimming group of these animals.

Batrachyla leptopus. Mihi.

Plate XVIII.—Fig. 5.

Description.—Head depressed, broad, rounded. Nostrils small, placed near together. Eyes large, opening considerably upwards. Tongue nearly round, the posterior part free for about one-third of its length. Palatine teeth placed in two small oval groups, placed obliquely, between the posterior nostrils, separated from each other by a considerable space. Tympanum small, nearly round. Limbs of moderate length. The toes on all the feet depressed, slender, the terminal dilatation very small, transverse, truncated; those of the fore feet connected at the base only, those of the hinder to the union of the first and second phalanges; of those of the fore feet the third is the longest, then the fourth, the second, and the first; of the hinder the fourth is the longest, then the third and fifth equal, then the second and the first. There are some minute scattered glands on the posterior part of the thighs.

The only specimen in Mr. Darwin’s collection is in so bad a condition, that it is impossible to say with any certainty what is its natural colour. It is brown above, with a lighter band across the head between the eyes, and there are traces of a longitudinal line down the back; the limbs are banded with brown and brownish yellow; the under parts are pale, dotted with brown.

Found by Mr. Darwin at Valdivia.

Genus—HYLORINA. Bell.

Caput subrotundum planum. Linguæ magnâ circularis, posticè libera. Dentes palatini in lineâ transversâ, parum interruptâ, dispositi. Tympanum distinctum. Digiti subdepressi, ad apicem obtusi, haud expansi; anteriores ferè liberi; posteriores ad basin membranâ connexi, et marginati. Femora multò glandulosa.

A genus nearly allied to Hylodes, from which, however, it may at once be distinguished by the palmure of the hinder toes—which in Hylodes are entirely free—and by the absence of even the slightest dilatation of their extremities; offering another example of an osculant form between the Hylidæ and the Ranidæ.

Hylorina sylvatica. Mihi.

Description.—Head broad, rounded, the anterior margin, from the nose to the lip, nearly perpendicular. Eyes large and prominent. Tympanum distinct, small, round. Tongue very large, circular, and entire, the posterior half free. Palatine teeth placed in a transverse line between the posterior nostrils, scarcely interrupted in the middle. Skin of the back rugose. Anterior feet with the toes long, rather slender, united at the base only by a very short membrane, with round subarticular tubercles, the apex rounded, but not presenting the slightest expansion. Hinder toes similarly formed, but with the connecting membrane more conspicuous, and extending along the sides of the toes nearly to the extremity. Thighs covered on the under and posterior surface with rather large and distinct glands.