408 



VERTEliKATA. 



OUDI-K 1. ANURA. 



Thi- animjils of this onlor, the name of whicli siixnifics tailless, have a short, squat body, four 

 legs, tlio hinder ones the K)nj,'est, a lari;c mouth ; the skin naked and extremely dilatable, in some 

 cases furnished with glands whi.-h secrete an acrid liquid; the eyes large and prominent; 

 the iipper jaw usually armed with small hooked teeth ; the tongue, though sometimes wanting, 

 generally of large size; the spinal column short, consisting, as a general rule, of eight verte- 

 brie. flie habits arc various, many living habitually in the water, while others only visit that 

 clement for depositing their ova, which give origin to tadpoles, the development of which we 

 shall hereafter notice. AVe shall describe these animals under three heads : Ranid^, or Frogs, 

 BuFONiD-«, or Toads, an<l PiPin.i:, or Surinam Toads. 



THE COMMON FROG. 



THE RA^^IDvE. 



The Frogs form the highest group of the Batrachian class. They are active creatures, feeding 

 on insects and worms. Those Avhich live upon the ground in the neighborhood of standing 

 water, and pass a cpnsiderable portion of their lives in the water, have their toes pointed, and 

 those of the hinder feet united, almost to the tips, by a membrane. 



Genus RANA : Rana. — This includes the Common Frog of Europe, R. temporaria, a very 

 abundant and well-known animal. It is constantly to be found hopping about in the neighbor- 

 hood of water, especially in damp evenings. It generally deposits its eggs in the Avater in the 

 month of March ; they are enveloped in a mass of gelatinous matter, within which the eggs are 

 seen gradually to increase in size for a month or five Aveeks, at the end of which time the young 

 tadpoles may be seen moving. When ready to enter upon their aquatic existence, they eat their 

 way through the surrounding jelly, and thus escape. In the course of six or eight Aveeks the 

 four legs are fully formed ; the tail then gradually disappears, and the young frog usually quits 

 the water immediately. In this way they often suddenly make their appearance in prodigious 

 numbers in particular spots, giA'ing rise to the popular superstition of " frog rains ;" and in some 

 cases it is said that the little creatures have been taken up and carried to a distance by high 

 winds, to the great astonishment of the inhabitants of the districts in Avhich they afterA\'ard 

 descended. 



The production of the young of these animals is so curious as to require a more detailed 

 description. The ova of the female are deposited in a jelly-like mass at the bottom of the water, 

 being impregnated by the male at the time of their passage. The development of the young is 



