“Come along; don’t stay poking in that ditch; it’s nothing but a common
frog,” said a lively-looking fellow to his companion; who replied,
“True, it is only a common frog, but give me a few minutes, and I will
endeavour to show you that it better deserves attention than many a
creature called rare and curious. The fact is, that the history of what
we call common animals, and see every day, is often very imperfectly
known, though possessing much to astonish and instruct us. Come, sit you
down on this bank for a few minutes, instead of pursuing your idle walk,
and I will endeavour to excite your curiosity and powers of observation.
If I do so by means of so humble an instrument as a common frog, I do
better service than if I were to fix your attention by accounts of the
mightiest monsters of fossil or existing Herpetology, as the part of
natural history which treats of reptiles is called. See! I have caught
him, and a fine stout fellow he is, for I perceive from his swelling
chops he is a male. Let us now consider his place in the creation:
it is in the tailless section of the fourth order of reptiles called
Batrachians, and distinguished from the other three orders by the absence
of scales on the skin, and by the young undergoing the most extensive
changes of form, organic structure, and habits of life. You know, I
presume, that frogs are hatched from eggs, or as they are called in mass,
spawn, which is laid early in the year in shallow pools, and resembles
boiled sago. The peasantry believe that as it is laid in more or less
deep water, so will the coming season be dry or wet. This, however, like
many other instances of supposed prescience in animals, does not stand
the test of observation, for spawn is frequently laid where, when the
weather proves fine, the water is dried up. Nevertheless, its position
does in some degree indicate the state of the atmosphere, as, under the
low pressure of air which precedes and attends rain, the spawn, owing
to bubbles of air entangled in it, floats more buoyantly, and is fitted
for shallower water than it could swim in under other circumstances.
But to our subject. The product of this spawn is in every thing unlike
the perfect frog we now behold. He commenced life with some twelve
hundred in family, a tiny, fish-formed creature, with curious external
gills, which in a short time became covered with skin; and he then
breathed by taking in water at the mouth, passing it over the gills,
and out at orifices on each side, just as we see in ordinary fishes.
The circulation of his blood was also similar to that of those animals.
His head and body were then confounded in one globular mass, to which
was appended a long, flattened, and powerful tail; his mouth was small,
his jaws suited to his food, which was vegetable, and his intestines
were four times longer in proportion than they are now. After some time
of this fish-like life, two limbs began to bud near to the junction of
his body and tail--then another pair under the skin near his gills. His
tail absorbed in proportion as his limbs developed, until, casting away
the last of his many tadpole skins, and with it his jaws and gills, he
emerged from the water a ‘gaping, wide-mouthed, waddling frog,’ to seek
on land his prey, in future to consist exclusively of worms, insects,
and other small living beings; still retaining his power of swimming
and diving, but accomplishing it by powerful exertions of his hinder
legs, which serve him on land to effect his prodigious jumps, of which we
may form an estimate by knowing that a man exerting as great a power in
proportion could jump upwards of one hundred yards. He cannot, however,
breathe under water; and though his skin, which possesses enormous
absorbing powers, may contribute a portion of the necessary stimulus to
his blood, yet he must breathe as we do by getting air into his lungs,
and therefore, except when he is torpid from cold, he cannot continue any
great length of time under water. Observe now his mode of breathing--see
with what regularity his nostrils open and shut, while the skin under
his throat falls and rises in the same order, for as he is without ribs
or diaphragm, his mode of inspiration is not effected as ours is; but
he takes air into his closely shut mouth through his nostrils, which he
then closes, and by a muscular exertion presses the air into his lungs.
Were you to keep his mouth open, he would be infallibly smothered. His
tongue is one of his most striking peculiarities, for instead of being
rooted, as in other animals, at the throat, it is fastened to his under
lip, and its point is directed to his stomach. Nevertheless, this strange
arrangement is well suited to his purposes, and his tongue as an organ of
prehension is very effective. It is flat, soft, and long, and is covered
with a very viscid fluid. When he wishes to use it, he lowers his under
jaw suddenly, and ejects and retracts his tongue with the rapidity of a
flash of light, snatching away a luckless worm or beetle attached, by
the secretion before alluded to, to its tip. The insertion of the tongue
in front of the lower jaw serves not only to aid mechanically in its
ejection and retraction, just as we manage the lash of a whip, but it
saves material in its construction, for it would require much greater
volume of muscle to accomplish the same end posited as tongues usually
are; and it has also the advantage of bringing the food into the proper
place for being swallowed, without further exertion than that of its
retraction.
Look now at the splendour of the golden iris of his eyes, and his
triple eyelids; see, notwithstanding the meagre developement of his
head, as a phrenologist would say, his great look of vivacity; though
his brain is small, his nerves are particularly large, and his muscles
are accordingly possessed of more than ordinary excitability, which
property has subjected his race to very many cruel experiments, at the
hands of physiologists, galvanists, &c. A favourite experiment was, by
the galvanic action of a silver coin and a small plate of zinc, on the
leg of a dead frog, to make it jump with more than the force of life.
Should you be inclined to study his anatomy, you will find ample stores
in the ponderous folios of old writers, who have so laboriously wrought
out his story as to leave little to be accomplished by us. The frog, now
abundantly dispersed over Ireland, was introduced into this country not
much more than a century since by Doctor Gwythers of Trinity College; and
in thus naturalizing this pretty creature, cold and clammy though it be,
he did a service, for it contributes materially to check the increase of
slugs and worms. I have often vindicated the frog from charges brought
against him by gardeners. I have been shown a strawberry, and desired
to look at the mischief he has done. I have pointed out, that the edge
where he was accused of biting out a piece was not only dry, but smaller
than the interior of the cavity, and it therefore could not be formed
by a bite. I have then shown other strawberries with similar wounds, in
which small black slugs were feeding; and I have cut up the supposed
strawberry-devouring frog slain by the gardener, and shown in his
stomach, with several earthworms, a number of little black slugs of the
species alluded to, but not one bit of fruit: thus proving, I hope, that
the cultivator of strawberries ought for his own sake to be the protector
of frogs.
The frog is a good instance of the confusion that constantly arises from
applying the same words to designate different animals in different
countries. The common frog of the continent is the green frog (_Rana
esculenta_), while our common frog is their red frog (_Rana temporaria_).
The former is of much more aquatic habits than the latter, and is not
known in Ireland. I once made an attempt to introduce it here, and when
in Paris directed a basket of 100 frogs to be made up for me, giving
special instructions that no _common_ frogs were to be amongst them,
which order I found on returning was obeyed as understood in that
country, and not a single green frog was in my lot, though I intended to
have none other. As articles of food there seems to be little difference,
but the preference is given to the green frog. The vulgar opinion that
Frenchmen eat frogs for want of better food is quite erroneous; the
contrary is the fact; for a fricassee of these animals is an expensive
dish in France, and is considered a delicacy. Its chief merit appears
to me to be its freedom from strong flavour of any kind; a delicate
stomach may indulge in it without fear of a feeling of repletion.
In this country the foolish prejudices which forbid the use of many
attainable articles of wholesome food, applies with force to frogs. Our
starving peasants loath what princes of other nations would banquet
on, and leave to badgers, hedgehogs, buzzards, herons, pike and trout,
sole possession of a very nutritive and pleasant article of food. When
devoured by the heron, it is in part converted into a source of wonder to
the unenlightened; for the curious masses of whitish jelly found on the
banks of rivers and other moist places, and said by the country people to
be fallen stars, are, so far as I have been able to observe, masses of
immature frog spawn in a semi-digested state; and they seemed to me to
have been rejected by herons, just as we see hawks and owls reject balls
of hair, feathers, or other indigestible portions of their prey.
While on the subject of eating frogs, one of many of my adventures with
the animal comes upon me with something like a feeling of compunction.
When I was at school, it happened on a great occasion that a party
of the ‘big boys’ were allowed to sit up much beyond the ordinary
time of retiring. Finding it cold, it was proposed to adjourn to the
kitchen, poke up the fire, and make warm before going to bed. Proceeding
accordingly, we were startled by the repetition of some heavy sounds on
the floor, and on getting up a blaze we discovered a frog of gigantic
proportions jumping across the room. He was seized, and a council being
held upon him, it was resolved that he should be killed, roasted, and
eaten; and this awful sentence was at once put into execution--the
curious for curiosity, the braggarts for bravado, and the cowards,
lest they be thought so, partaking of the repast. We discovered next
day that the unfortunate devoured had been for three years a settled
denizen of the kitchen, where he dealt nightly havoc on the hordes of
crickets and cockroaches it contained. I have had for three years a frog
in confinement where his food is not very abundant, and he has grown
proportionally slowly, being still of a very diminutive size. Linnæus and
others distinguished ours as the mute frog, believing it did not possess
a voice. They were mistaken: you hear our captive, when I press his back,
give utterance to his woes; but if you desire to attend his concert, get
up some bright night in spring, seek out his spawning place about the
witching hour, and you will then hear sounds, of strange power, which
seem to make the earth on which you stand to tremble. On investigation
you will find it to proceed from an assembled congregation of frogs,
each pronouncing the word _Croak_, but dwelling, as a musician would
say, with a thrill on the letter _r_. When speaking of the tadpole, I
forgot to allude to the fact, that recent experimenters find that by
placing them in covered jars, the developement of the frog is arrested.
The tadpole will continue to grow until it reaches a size as great as
that of an adult frog. This has been attributed by the discoverer to
a withdrawal of the agency of light; but it strikes me he has, in his
anxiety to prop a theory, lost sight of the true reason, which appears to
be, that while he excluded the young animal from light, he also put it
in such a situation as to compel it to breathe alone by its gills, and
afford it no opportunity for the developement of its lungs, and so it
retained of necessity its fish-like functions. As you are probably more
of a sportsman than a naturalist, you have observed in rail shooting,
your pointer, after a show of setting, roll on the ground: if you had
examined, the chances are you would have found a dead frog of no very
pleasing perfume. Why the dog so rolled, I cannot say, unless it be, that
he like other puppies wished to smear his hair with nasty animal odours.
I have now I think worked out your patience; and though I could dwell
much longer on the subject, and eke out much from ancient lore, I will
end by a less pompous quotation of part of a well-known song--
‘A frog he would a-wooing go,
Whether his mother would let him or no.’
And the catastrophe,
‘A lily white duck came and gobbled him up.’
Pray apply the moral. Had the said frog had his mind cultivated, and
had he been acquainted with nature, he would not have engaged in a
thoughtless courtship, that could have no good end, nor have disobeyed
the voice of experience, and so met with the fate that awaited him. You
may now go on your walk; and if a common frog cannot interest you, take
care of the lily white duck.”