The Wit of the Wild 



r 



frog to take a firm grasp of whatever he 

 touches. 



This is really a very interesting bit of mech- 

 anism. The holding-power seems really due 

 to the fact that all air is pressed out from be- 

 neath the pad of the toe, rather than to either 

 suction (certainly not exerted) or the stickiness 

 of the secretion, although the latter helps. The 

 matter was experimentally studied by the Ger- 

 man naturalist Schuberg, who found that he 

 could support more than the weight of one of 

 these frogs from a bit of glass merely moistened 

 and pressed against another glass surface. The 

 glass sides of a case or fernery, in which these 

 frogs are kept captive, will soon be smeared 

 with their finger-marks. 



In addition to this, the lower half of the abdo- 

 men (where the skin is thick and porous) also 

 exudes a sticky liquid, so that when the animal 

 sits pressed against the bark of a tree-trunk, or 

 any other upright surface, he is really glued 

 there, and thus supports his weight more easily 

 than if he clung with his hands and feet alone. 

 All the same, he likes to sit in a comfortable 

 *$ 212 



