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THE CRAWLING BATRACHIANS. 



This curious species inhabits Mexico, and can easily be recognized by the peculiar 

 form of its head, which is rounded, merged into the body, and has the muzzle abruptly 

 truncated, so as to form a small circular disc in front. The gape is extremely small, 

 and the head would, if separated, be hardly recognizable as having belonged to a Frog. 

 There are two glands by the ears, but although they are of considerable dimensions, 

 they are scarcely apparent externally, being concealed under the skin. The legs are 

 very short and thick, and the feet are half-webbed. Each hind foot is furnished with 

 a flat, oval, horny spur formed by the development of one of the bones. There are 

 no teeth in the jaws, and the ear is imperfect. The color of the Rhinophryne is slate- 

 gray, with yellow spots on the sides and a row of similar spots along the back. Some- 

 times these latter spots unite so as to form a jagged line down the back. 



RHINOPHRYNE. - 



WE now arrive at the Crawling Batrachians, technically called Amphibia Gradientia. 

 All these creatures have a much elongated body, a tail which is never thrown off as in 

 the frogs and toads, and limbs nearly equal in development, but never very powerful. 

 Like the preceding sub-order, the young are hatched from eggs, pass through the pre- 

 liminary or tadpole state, and, except in a very few instances, the gills are lost when 

 the animal attains its perfect form. Both jaws are furnished with teeth, and the palate 

 is toothed in some species. The skin is without scales, and either smoothed or 

 covered with wart-like excrescences. There is no true breast-bone, but some species 

 have ribs. 



The development of the young from the egg is not quite the same as that of the tail- 

 less Batrachians. Instead of being deposited in masses or long strings, the eggs are 

 laid singly, and are hatched in succession. When the young are first hatched they bear 

 some resemblance to the tadpole of the frog, the gills being very conspicuous. In 

 these creatures, however, the fore-legs make their appearance first, and are soon 

 followed by the hinder pair, whereas in the frogs the hind-legs are seen for some time 

 before the fore-limbs are visible externally. Further remarks will be made on this 

 subject when we come to our well-known representative of this sub-order, the common 

 newt or eft. 



