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tamed; he remembers the freedom he has lost, and is always 
ready to revenge himself upon the hand of his captor. 
With regard to the strength of the viper’s poison, I may 
mention the experience of Professor Rupert Jones, who told 
me that he saw a very little viper, about six inches long, crossing 
a road, and presented his finger to it, which the reptile at once 
struck, inflicting a painful wound. Mr Jones’s hand swelled, 
and the sting was, he said, as painful as that of a wasp. 
Barracuta.—The common Frog (Rana temporaria) is plen- 
tiful, but not so common as the toad. I believe that the 
numbers of the frog depend upon the abundance of water-fowl 
in any given district. The frog has no ribs, and therefore he 
cannot inflate his lungs, as higher animals do, by an effort of 
the chest, but he must force air into his lungs by means of 
the muscular construction of his throat and mouth; in fact 
he gulps the air into his lungs, and in so doing causes that 
pulsating undulation beneath the throat so clearly observable 
when the creature is at rest. Little effort is necessary in 
expiration, as the constricting muscles of tle lungs naturally 
contract when the air is allowed to escape. In consequence 
of this construction of the organs of respiration the frog quickly 
dies if his mouth be propped open, as in this position he cannot 
force the air into his lungs. I have revived frogs which had 
become insensible from suffocation, by opening their mouths 
and blowing violently into them. 
The frog aerates some portion of his blood by means of 
his skin, which must be moist, to ensure healthy action. 
In summer, when ditches and roadside pools are dry, the 
frog absorbs the necessary moisture from the dew, and when 
rain falls he hops out of his retreat in the wall or hedgerow 
and enjoys a shower-bath. 
The frog has a voice. His song is not distinguished for 
that sweetness and enthusiasm which are so charming in the 
notes of our woodland birds, but the sound is not unmusical. 
When seized by a snake the frog will sometimes scream 
like a child, and so loudly that I have known a dog lying 
asleep at a distance of twenty yards spring up, on hearing 
