Our frogs and toads are not likely at present to become an affliction to us. Should they ever do so I must certainly send for some Irish leather, or, failing that, for a pinch of Irish dust, and try its effect upon them. An influence that has been vouched for by such a variety of authorities ought to retain something of its ancient potency. Scientific experiments in any case are always interesting!
Returning to our pond this morning to see whether the water-lilies propose flowering this season, I find that the frogs have been depositing spawn along its edges, so that the thongs of Irish leather may become necessary sooner than I expected!
All the same I am delighted to see the frog-spawn, for I have an affection for tadpoles. Youthful associations cluster pretty thickly around them, but apart from such a merely sentimental attachment, there is a satisfaction, I may say a zoologic thrill, about this transition of a water-living and water-breathing animal into an air-breathing one; a transition going on, moreover, not at some remote, and more or less dubious geologic age, but under one’s very eyes, even, as in this case, in the middle of one’s own decorous, shaven lawn.
It is difficult to remember that frogs breathe air as much as we do ourselves. Unlike ourselves, and their other zoologic betters, they do so, however, not by alternate contractions and dilations of the chest, Nature not having provided them with ribs, but by the doubtless more archaic process of swallowing air. Not only would a frog die if kept too long under water, but--seeing that it can only swallow air by shutting its mouth--were that mouth kept forcibly open it would equally die, and from the same cause, namely, want of breath. Tadpoles, on the other hand, are strictly water-breathers, and until they have shed their gills, have no more need to go to the surface to breathe than a fish has. That, by the way is not an absolutely accurate illustration, seeing that certain fishes _do_ need to go to the surface for air. The famous Anabas, or “climbing perch” of India, is such an air-breathing fish, the air reaching it by means of cavities on either side of its gills, and if prevented from reaching the surface, and renewing the supply, it would “drown like a dog,” or so the scientists assert. Such cases, however, can hardly be called normal. Fishes that can live comfortably for days out of the water, that can nest in a bush, and travel across a particularly dry country, are not likely to be met with in zoologic rambles about this parish.