The method in which toads procreate and bring forth, seems to be very much in the dark. Some authors say that they are viviparous ; and yet Ray classes them among his oviparous animals, and is silent with regard to the manner of their bringing forth. Perhaps they may be ἔσω μὲν ὠοτὸκοι, ἔξω δε ζωοτόκοι, as is known to be the case with the viper.*

The copulation of frogs (or at least the appearance of itfor Swammerdam proves that the male has no penis intrans) is notorious to every body; because we see them sticking upon each other's backs, for a month together, in the spring; and

of this fish (the situation of the roe in most fishes) is the roe. Contrary to what is found in most species of fish, this roe contains a large quantity of fine oil, so free from fishy flavour, as to be commonly employed (at least that found in the conger) in crust and other culinary uses in Cornwall. In the fish, its use seems to be to protect the delicate sexual organs from cold. The whole constitution of the eel is remarkably susceptible of cold; it feels every change of temperature. There are no eels in the Danube, nor in any of its tributary streams. The rivers of Siberia, though large and numerous, are destitute of them."

It appears pretty evident that eels are not viviparous, although this opinion has long prevailed amongst naturalists.

That snakes are oviparous there can be little doubt. A correspondent in the Magazine of Natural History, iv. p. 268, having killed an adder in Essex, opened it, and "discovered a string of eggs, fourteen in number, in each of which was a young adder, perfectly formed, and enveloped in a glutinous fluid. These little creatures, although they had never seen the light, were lively, and, I thought, even evinced an inclination to bite. I took some of them out of the eggs, and they soon died but those which were laid on a piece of paper, with their envelope unbroken, were alive and active many hours afterwards. As may be supposed, the present animal was now in nearly an empty state; but, on examining its heart, I perceived that it was still strongly convulsed. I removed it with a penknife; and, laying it on a piece of white paper, was much interested in watching its motions. It continued to beat, with little abatement of force, for an hour, when its palpitations, though strong, became less rapid; and ceased in half an hour more."-ED.

* Toads procreate exactly in the same manner as frogs, and are also oviparous. The eggs are imbued by the spermatic fluid of the male, at the time of their extrusion. The eggs of frogs are deposited in water, in irregular congeries, while those of the toad are extruded in catinated strings. Schneider, a zealous observer of nature, affirms, that toads eat the skin which they cast periodically. This fact has been confirmed by Mr Bell, in a paper in the Zoological Journal.

The manner in which a frog takes his prey is very curious. When he first notices a worm or fly, he makes a point at it, like a pointer dog setting game. After a pause of some seconds, the frog makes a dart at the worm, endeavouring to seize it with his mouth; in which attempt he frequently fails more than once, and generally waits for a short interval before he renews the attack.-ED.

yet I never saw, or read of toads being observed in the same situation. It is strange that the matter with regard to the venom of toads has not been yet settled. That they are not noxious to some animals is plain; for ducks, buzzards, owls, stone-curlews, and snakes, eat them, to my knowledge, with impunity. And I well remember the time, but was not eyewitness to the fact, (though numbers of persons were,) when a quack, at this village, ate a toad to make the country people stare afterwards he drank oil.

I have been informed also, from undoubted authority, that some ladies (ladies, you will say, of peculiar taste) took a fancy to a toad, which they nourished, summer after summer, for many years, till he grew to a monstrous size, with the maggots which turn to flesh flies. The reptile used to come forth, every evening, from a hole under the garden steps; and was taken up, after supper, on the table to be fed. But at last a tame raven, kenning him as he put forth his head, gave him such a severe stroke with his horny beak, as put out one eye. After this accident, the creature languished for some time, and died.

I need not remind a gentleman of your extensive reading, of the excellent account there is from 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; shewing, 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

*The following paragraph is extracted from a late number of the Belfast Chronicle:- "As two gentlemen were sitting conversing on a causey pillar, near Bushmills, they were very much surprised by an unusually heavy shower of frogs, half formed, falling in all directions; some of which are preserved in spirits of wine, and are now exhibited to the curious by the two resident apothecaries in Bushmills." Mr Loudon says,"When at Rouen, in September, 1828, I was assured by an Englisk. family, resident there, that, during a very heavy thunder shower, accompanied by violent wind, and almost midnight darkness, an innumerable multitude of young frogs fell on and around the house. The roof, the window-sills, and the gravel walks, were covered with them; they were very small, but perfectly formed; all dead; and the next day being excessively hot, they were dried up to so many points, or pills, about the size of the heads of pins. The most obvious way of accounting for this phenomenon, is by supposing the water and frogs of some adjacent ponds to have been taken up by wind in a sort of whirl, or tornado."-Mag. of Nat. Hist. ii. p. 103.

We have records of this kind, in all ages; and I have selected the above

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 fishlike 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 to 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 the 5th, 1766, in his account of the mud inguana, an amphibious bipes 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

two recent instances, to prove that our author is wrong. A shower of young herrings fell in Kinross-shire, about ten years ago, many of which were picked up, in the fields around Loch Leven, by persons with whom I am acquainted. The reason why frogs go abroad during showers, is thus accounted for by Dr Townson, founded on certain experiments which he instituted regarding them. He says, "That frogs take in their supply of liquid through the skin alone, all the aqueous fluids which they imbibe being absorbed by the skin, and all they reject being transpired through it. One frog, in an hour and a half, absorbed nearly its own weight of water."-ED.

*It has never been verified that the tree-frog is a native of Britain. But Mr Don discovered the edible frog, rana esculenta, in the neighbourhood of lakes in Forfarshire. This species is principally distinguished from the common one, by its larger size, and having three longitudinal yellow lines on its back.-ED.

become land animals, as I have observed, by keeping them alive for some time, myself." *

Linnæus, in his Systema Naturæ, hints at what Mr Ellis advances more than once.

Providence has been so indulgent to us as to allow of but one venomous reptile of the serpent kind in these kingdoms, and that is the viper. As you propose the good of mankind to be an object of your publications, you will not omit to mention common salad oil as a sovereign remedy against the bite of the viper. As to the blind worm, (anguis fragilis, so called because it snaps in sunder with a small blow,) I have found, on examination, that it is perfectly innocuous. A neighbouring yeoman (to whom I am indebted for some good hints) killed and opened a female viper about the 27th of May he found her filled with a chain of eleven eggs, about the size of those of a blackbird; but none of them were advanced so far towards a state of maturity as to contain any rudiments of young. Though they are oviparous, yet they are viviparous also, hatching their young within their bellies, and then bringing them forth. Whereas snakes lay chains of eggs every summer in my melon beds, in spite of all that my people can do to prevent them; which eggs do not hatch till the spring following, as I have often experienced. Several intelligent folks assure me, that they have seen the viper open her mouth and admit her helpless young down her throat on sudden surprises, just as the female opossum does her brood into the pouch under her belly, upon the like emergencies; and yet the London viper catchers insist on it, to Mr Barrington, that no such thing ever happens. The serpent kind eat, I believe, but once in a year; or, rather, but only just at one season of the year.† Country people talk much of a water snake, but, I am pretty sure, without any reason; for the common snake (coluber natrix) delights much

* In an excellent paper on this subject, in the seventeenth numoer of the Edinburgh Philosophical Journal, the metamorphoses of these animals are well described; from which it would appear, that the aquatic salamander is three years of being capable of reproducing; that its first change from the egg is to the tadpole state, and that it undergoes several changes in progressing to maturity. Er.

+ All the snake tribe eat only periodically, but it is a mistake to suppose they feed but once a year, or at a particular time of the year. After having gorged their prey, they are overcome by a sleepy torpor, and remain for days, and sometimes even weeks, in this state, when they again become lively, and crawl abroad in quest of prey. Most of the tribe, like nearly the whole amphibia, cast their skins periodically. - ED.

to sport in the water, perhaps with a view to procure frogs, and other food. *

I cannot well guess how yon are to make out your twelve species of reptiles, unless it be by the various species, or rather varieties, of our lacerti, of which Ray enumerates five. † I have not had opportunity of ascertaining these, but remember well to have seen, formerly, several beautiful green lacerti on the sunny sandbanks near Farnham, in Surrey; and Ray admits there are such in Ireland.

LETTER XVIII.

TO THOMAS PENNANT, ESQ.

SELBORNE, July 27, 1768.

DEAR SIR,-I received your obliging and communicative letter of June the 28th, while I was on a visit at a gentleman's house, where I had neither books to turn to, nor leisure to sit down, to return you an answer to many queries, which I wanted to resolve in the best manner that I am able.

A person, by my order, has searched our brooks, but could find no such fish as the gasterosteus pungitius; he found the gasterosteus aculeatus in plenty. This morning, in a basket, I packed a little earthen pot full of wet moss, and in it some sticklebacks, male and female, the females big with spawn ; some lamperns; some bull-heads; but I could procure no minnows. This basket will be in Fleet Street by eight this evening; so I hope Mazel will have them fresh and fair

*The whole of the snake tribe take the water: we have numerous records of this fact. They swim with much ease, and in America frequently cross the great rivers. The natives say they catch fish. Mr Murray mentions a curious instance of an adder having seized the artificial fly of an individual fishing in one of the lakes of Scotland, on the verge of the estuary of a river. It was finally drowned by dragging it into the current against the stream.

On the 2d August, 1828, a fisherman caught a specimen of the ringedsnake, (coluber natrix of Linnæus,) while fishing in Haslar Lake, one of the branches of Portsmouth Harbour; and, on the following morning, a seaman caught another at the same place, both of which were brought to Mr Slight, surgeon, Portsmouth.-ÉD.

There have been just twelve species of reptiles discovered in Britain up to the present time.-ED.

The gusterosteus pungitius, or ten-spined stickleback, is very common in our rivers and in estuaries; few British species have been ascertained. Besides the above two, there are the g. trachurus, g. semiarmatus, and g. leiurus. See note at page 26.-ED.