2/0 ANURA CHAP. 



name esculenta needs no comment, and this species is as much a 

 martyr to science as the brown Grass-frog. The destroyers of 

 tadpoles and young frogs are unlimited. In their turn the 

 frogs themselves, especially the old ones, are very rapacious, and 

 eat any living creature they can master, insects, worms and 

 snails, other frogs, especially the brown kind, and the young 

 brood of fishes. 



Kecently caught Water-frogs are wild beyond description, 

 much more so than the Grass-frog, but even they calm down 

 after some time, learn to know their keeper, and allow him to 

 handle them without trying to commit suicide by jumping on 

 to, into, and down anything. However, they do not thrive well 

 in captivity, and it is rare that they can be induced to breed, 

 unless their enforced new home affords them ample freedom, 

 and plenty of water and fresh air. 



The Water-frogs appear in Germany rather late in the year, 

 not before the middle of April, first the younger, then the adult 

 members. In Southern Europe they show themselves earlier, 

 and still further south they do not hibernate at all. The breed- 

 ing season begins in Germany towards the end of May and 

 continues well into June, the var. ridibunda beginning mostly a 

 fortnight earlier. The male clasps the female under the arms, 

 throwing its own round her breast, the nuptial grey excrescences 

 on his inner fingers pressing against her skin, the palms being 

 turned outwards. The embrace does not last long, rarely 

 extending over a few days. The eggs, to the astonishing number 

 of 5000 to 10,000 in full-grown specimens, are expelled in 

 several masses, which sink down and remain at the bottom. 

 The eggs measure only 1*5 mm. and are yellowish-grey above, 

 pale yellow below ; their gelatinous cover swells to 7-8 mm. in 

 width. The embryo escapes on the fifth or sixth day as a very 

 small larva, in which, however, the mouth, eyes, and beginnings 

 of the external gills are already discernible. At the age of two 

 weeks the gills have shrunk away, the left-sided " spiracle " is 

 completed, and the well -tailed tadpoles, olive brown above, 

 yellowish white below, still hang with their suckers on to plants 

 and stones, or lie at the bottom, nibbling away at any rotting 

 animal matter or scraping off the green algae. 



It may here be mentioned that small tadpoles of any kind 

 can with advantage be used as cleaners of delicate and small 



