FROGS AND TOADS. 457 



there are two varieties, differing from one anotlier in colour — is properly a 

 native of the Continent, it has been introduced into the fens of Cambridge 

 and Norfolk, where it seems to flourish. It has a very extensive geographical 

 range, being found as far south as North-Western Africa, and as far east as 

 Japan. Although the species is the only one eaten in Europe, other 

 members of the sub-order are sent to table in distant lands, and the writer 

 has partakon of a dish of frogs in Argentina which belonged to a 

 totally different family. The great relative length of the hind-legs and 

 generally slender form of the body serves to cSstinguish the agile frog ; 

 while the fourth and fifth of the species mentioned above differ from the rest 

 by their spotted bellies. All these frogs are comparatively small creatures, 

 which are greatly exceeded in size by species from more distant lands. 



Among these, the bull-frog {R. cateshyana) of Eastern North America 

 occupies an intermediate position in this respect ; the largest member of the 

 whole genus being the Solomon Island frog {B. (juppyi), which grows to nine 

 inches in length, exclusive of the limbs. The habits of the connnon frog are 

 too familiar to need description ; and it is probable that like this species, all 

 the members of the genus take to the water at the time of breeding. Some 

 are, however, more aquatic than others ; and there are also certain frogs of 

 this genus which are partially arboreal in their habits, while others have 

 taken to burrowing in the ground. The climbing species have the tips of the 

 toes expanded into discs, but smaller 

 expansions may be present in the 

 aquatic kinds. An Indian species 

 (B. breviceps) makes burrows in the 

 ground to a depth of about eighteen 

 inches. Omitting mention of most of 

 the other numerous genera of this 

 extensive family, attention must be 

 concentrated on the curious flying- 

 frogs constituting the genus Bhaco- 

 pliorus. These frogs — -of which there 

 are more than forty species from the 

 Oriental countries and the island of 

 Madagascar — have the tips of both 

 pairs of feet expanded into large discs, 

 and very generally the front pair are 

 as fully webbed as the hinder, although 



in some kinds the webs of the former pig 2.— Flying ¥Rool.Rhacophorus). 



are less fully developed. The eyes 

 are remarkable for their fulness and brilliancy ; and the general hue of the 

 skin is bright green. Some species, are, however, stated to have the power 

 of changing their hue to harmonise with their surroundings. In the skeleton 

 of many of the species the tips of the terminal joints of the toes are in the 

 form of the letter Y. Except during the breeding season, when they doubt- 

 less take to the water, these frogs are arboreal in their habits. They derive 

 their name of flying frogs from a statement to the effect that one species at 

 least has been observed to take a long flying leap from a tree, apparently 

 supported by the large webs between the toes. Although it does not ajipear 

 that such a feat has ever been witnessed by a European observer, it is almost 

 incredible that the sole use of these huge webs is for swimming, more especi- 

 ally since these frogs pass but a comparatively small portion of their existence 



