British Amphibians : Toads and Frogs 



Partridges are calling in the cornfields, the aquatic 

 denizens of the marshes croak on far into the night. It 

 is then that the voice of the Natterjack is heard in the 

 land — yet only in regions somewhat proscribed. 



The Common Frog (Rana temporaria, Plate I.). 



Practically all over the British Isles the Frog is a 

 well-known frequenter of ponds, ditches, pools, or 

 marshy lands. It is said to have been introduced into 

 Ireland early in the eighteenth century, and to-day is 

 considered as worthy of a place in the fauna of that 

 island. 



The Frog's year opens usually in late March, when 

 the spawn may be found about the numerous waterways. 

 The eggs are small, round, opaque bodies encased in a 

 protective covering, gelatinous in character, and usually 

 clustered together. These masses sink to the bottom 

 of the pool, where they swell perceptibly until they 

 attain a buoyancy that forces them to the surface of the 

 water. The Tadpoles, on issuing from their envelopes, 

 have gills with a fleshy sucker beneath the head. By 

 the latter appendage they are enabled to hold firmly to 

 any object the sway of the water may drive them 

 against. There is a depression on the under side of the 

 head that later becomes active, and ultimately opens, 

 fashioning the alimentary canal. This enables the 

 creature to feed upon the tender and succulent vegeta- 

 tion within its reach. Then this sucker splits in twain, 

 the external gills are replaced by internal substitutes 



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