40 THE BIOLOGY OF THE SEASONS 



Before leaving the tadpoles, interesting in so many 

 ways, let us think over the year's life of the frog. Through- 

 out the winter months the frogs lie near the pond, buried 

 in the mud, mouth shut, nose shut, eyes shut, with the 

 heart beating feebly, breathing through their skin, and 

 eating nothing. The awakening in Spring is followed 

 immediately by pairing and egg-laying, and the aquatic 

 juvenile life of the tadpoles occupies about three months. 

 In summer there is a remarkable migration to the fields 

 and meadows, and many hundreds of froglings, about the 

 size of a first-finger nail, are seen on the march from 

 the pond. The adults also migrate, and the meaning in 

 both cases is the same that they seek out places where 

 insects abound. Of the many that go forth, only a remnant 

 returns, for there is great mortality in the fields, where 

 there are many physical risks and many alert enemies. The 

 grass snake alone accounts for a good many in some parts 

 of England. Those that escape whether youngsters or 

 old experienced hands return to the pond in the autumn, 

 and go into winter-quarters in the mud. 



