FROGS AND TOADS 
more or less completely aquatic life. The frogs are more 
aquatic than many toads. In external appearance 
these amphibians differ mainly in colour, and in the 
degree of wartiness or smoothness which they show. 
It is plain that the most salient mark of difference from 
the Urodela is the restricted tail and the fact that they 
never possess in the adult condition either gills or gill 
slits. Their fingers and toes, moreover, are never reduced 
in number, and never, of course, vanish altogether as 
they do in some of the snake-like Urodeles. 
THE SURINAM TOAD 
One of the very oddest productions in the frog line 
is the Pipa americana. It isso flat that it seems almost 
to consist of matter arranged in two dimensions only. The 
head is small and the front edge of it garnished with 
many little papilla. The toes end in star-shaped pro- 
cesses, and the hind feet are webbed with unusual con- 
spicuousness. The toad has got no teeth at all; but 
it makes up for this incapacity for offence by a consider- 
able capacity for defence. Its body is covered with many 
little poison glands, with which are sometimes associated 
little spikes. Most persons have seen a young dog 
rashly take into its mouth a common toad, and then 
rapidly drop it; this sudden change of intent is due 
to the secretion by the toad of a poisonous liquid. The 
Surinam toad possesses the same properties in a higher 
degree. The flatness of this amphibian shows that it 
is intended for a purely aquatic life; and as a matter 
of fact it does not leave the water. It is harboured in 
pools in Guiana and perhaps in other parts of South 
America. It has a method of attending to its young 
that in all its details is unequalled in the frog tribe. 
The common frog of this country, when it goes a-wooing, 
leaves its offspring in the form of those masses of eggs 
embedded in jelly which are familiar to everybody. 
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