A unique method of egg protection has been evolved in many Old 
World tree frogs. The spawn are usually suspended above the water and 
then whipped into a foam with the hind legs. Thus air is beaten into the 
egg mass to supply the embryo with oxygen, since the surface of the foam 
develops a protective crust. When the eggs hatch, the tadpoles easily slide 
into the water. 
Tree frogs are not considered very intelligent members of their order. 
However, they are famed as weather prophets, and farmfolk are familiar 
with their lively chirpings which precede rainy weather. 
TYPICAL FROGS 
Frogs are versatile little creatures, a short survey of their accomplish¬ 
ments reveals. King of all frogs is the foot-long giant or goliath frog 
found in the sluggish streams of the Cameroons in West Africa. It can 
easily kill a large rat. Natives of the region prize the thigh bones of the 
giant for ceremonial purposes. 
The young of the Solomon Island frog undergo complete metamor¬ 
phosis within the egg and hop about as soon as they are hatched. In India 
the skating frog outdoes the fakir by jumping from the water, landing on 
the surface, and then taking off again. The Seychelles frog carries its dozen 
or so tadpoles on its back, to which they cling by means of their adhesive 
undersides. It is believed that they go through their entire development 
in this position. A skinny parachutist is the “flying” frog, which with its 
webbed hind and forelegs can glide safely from trees to the ground. 
The poison frog secretes a toxic substance which the Indians of South 
America use to poison arrows and dye parrot feathers. The latter turn 
green and yellow when rubbed on the frog’s back, which is spotted green, 
yellow and cherry. Despite its toxic effect on others, the poison frog is a 
good father to its tadpoles which it transports on “frog back” from the 
site where the eggs were laid to the nearest pool. Enlarged vocal sacs 
cover the entire undersurface of the male Darwin frogs and serve as 
an incubator for the larvae. The male picks up the eggs in his mouth and 
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