REPTILIA. 259 



a web between the toes of the hinder feet. The European genus Alytes is 

 remai'kable for the peculiar habit exhibited by the single species with 

 regard to its eggs. When these have been deposited by the female, the 

 male takes possession of them, and wrapping them round his body repairs 

 to some moist spot, where he remains patiently until they are nearly ready 

 to become disclosed, upon which he carries them to the water, this being 

 the proper element of the tadpoles. This habit will recall to the mind of 

 our reader what has been said of Desmogna*hus. Pelobates fusciis is 

 represented m pi. 81, fg. 38 ab; Bomhinator igneus, m jig. Slab; both 

 European. 



The family of HyladcB, known by the dilated toes, is almost entirely 

 arboreal in its habits. While the Ranidce dwell in the marshes and wet 

 places of the earth's surface, and the Bufonidce live on the drier land, the 

 HyladcB are mostly to be sought for among the thick foliage of trees, where 

 they make the woods resound with their piping melody. They are espe- 

 cially abundant in the dense forests of tropical regions, where they occur 

 of various shades of color, among which the green of the leaf and the grey 

 of the bark predominate. In the spring of the year they betake themselves 

 to the water for the purpose of reproduction ; and the tadpole undergoes 

 the same changes which we have described in the case of the true frogs. 



The genera of HxjladcB, found in North America, are but two. Hxjla is 

 known by the semi-palmated toes with very decided disks, by means of 

 which it can adhere with great tenacity to any surface, even that of glass. 

 The slightly emarginated tongue is round or oval. Here belong the well 

 known tree frogs, the two best known species of which are H. versicolor, 

 so similar to the European H. viridis (pi. 90, fig. 6, female, pi. 81, fig. 35, 

 male), and H. lateralis. The species H. pickeringii, possibly constituting 

 a separate genus, lays its eggs singly on submerged grass, and they develope 

 in the very short space of three days. The remaining genus, Acris, has a 

 cordiform tongue, and the dilatations of the toes are less conspicuous. The 

 species of this genus are not arboreal, being found principally among the 

 high grass of marshes and streams. It is among the Bufonidce that we are 

 to look for the highest development of the anourous batrachian structure. 

 Most species are far from presenting that variety of colors, that freshness 

 of appearance, and agility of movement, which make the frogs so con- 

 spicuous. They are not confined to the vicinity of water, but inhabit 

 districts in which but little moisture exists, and remaining concealed 

 during the day, emerge at night to gather up such insect food as they may 

 chance to come across. Species of the typical genus of this family, Bufo, 

 or the toad, although repulsive in their appearance, are yet perfectly 

 harmless in themselves, and may be of great benefit to the horticulturist, 

 in devouring large numbers of insects injurious to vegetation. A milky 

 juice exudes from the skin of most species, secreted by special glands : this, 

 in some species, is quite acrid, while in others it is entirely free from any 

 such property. A striking difference is observed between the frogs and 

 true toads, in the manner in which the ova are laid in the water. In the 

 former they appear as amorphous, generally globular masses, enveloped in 



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