om Mr. Derham, in Ray's "Wisdom of God in the
Creation" (p. 365), concerning the migration of frogs from their breeding
ponds. In this account he at once subverts that foolish opinion of their
dropping from the clouds in rain, showing that it is from the grateful
coolness and moisture of those showers that they are tempted to set out
on their travels, which they defer till those fall. Frogs are as yet in
their tadpole state; but, in a few weeks, our lanes, paths, fields, will
swarm for a few days with myriads of those emigrants, no larger than my
little finger nail. Swammerdam gives a most accurate account of the
method and situation in which the male impregnates the spawn of the
female. How wonderful is the economy of Providence with regard to the
limbs of so vile a reptile! While it is an aquatic it has a fish-like
tail, and no legs; as soon as the legs sprout, the tail drops off as
useless, and the animal betakes itself to the land!

Merret, I trust, is widely mistaken when he advances that the _rana
arborea_ is an English reptile; it abounds in Germany and Switzerland.

It is to be remembered that the _salamandra aquatica_ of Ray (the
water-newt or eft) will frequently bite at the angler's bait, and is
often caught on his hook. I used take it for granted that the
_salamandra aquatica_ was hatched, lived, and died, in the water. But
John Ellis, Esq., F.R.S. (the coralline Ellis), asserts, in a letter to
the Royal Society, dated June 5th, 1766, in his account of the _mud
inguana_, an amphibious biped from South Carolina, that the water-eft, or
newt, is only the larva of the land-eft, as tadpoles are of frogs. Lest
I should be suspected to misunderstand his meaning, I shall give it in
his own words. Speaking of the _opercula_ or coverings to the gills of
the _mud inguana_, he proceeds to say that, "The form of these pennated
coverings approaches very near to what I have some time ago observed in
the larva or aquatic state of our English _lacerta_, known by the name
of eft, or newt, which serve them for coverings to their gills, and for
fins to swim with while in this state; and which they lose, as well as
the fins of their tails, when they change their state and become land
animals, as I have observed, by keeping them alive for some time myself."

Linnaeus, in his "Systema Naturae," hints at what Mr. Ellis advances more
than once.

Providence has been so indulgent to us as to allow of but one venomous
rept