342 THE VIVARIUM. 
marked with fairly regular large spots, and dark cross-bars on the 
thighs. The sides of the thighs are yellow, edged with red. 
The under parts are of a uniform whitish colour. The male may 
be known by a dark-coloured external subgular vocal sac. 
The general shape of this Tree-frog is somewhat like that of its 
FIG. 85.—THE EUROPEAN GREEN TREE-FROu (Hyla arborea). 
near relative, the Toad. It makes a good deal of noise during 
damp weather. 
The European Green Tree-frog (Hyla arborea, Fig. 85), though 
so common and easily obtained, is one of the most charming 
