THE Batrachians are not by any means such strangers as some people may imagine. The reader who has forgotten his Greek, or who never had any Greek to forget, may fail to recognise them, but they have amongst them many old familiar faces for all that.

Let nobody, therefore, run away with the notion that this same ancient order is some old, broken-up, deadand-gone fraternity, similar to those illustrious orders of Odd Fellows, Green Foresters, Ancient Druids, and the like, which still find countenance and support amongst the children of men. The idea is altogether beside the mark. The Batrachians do not belong to the human family at all. They are a race, not of men, but of reptiles, the best-known members of the order being the small deer' enumerated above, from that extraordinary list of dainties which the banished Edgar palms off upon his father as his "food for seven long year."

No one will dispute that these little fellows are for the most part familiar enough; and yet how far removed are they from being familiar friends! The truth is, the Batrachians have but few admirers. They labour under that direst of misfortunes-a bad name. Innocent and inoffensive, and doing no small amount of good in their way, they are yet misrepresented and maligned, their good qualities denied, and bad qualities from which they are wholly exempt obstinately laid to their charge. There is perhaps hardly VOL. XXVII.-DECEMBER 1858.

another race of creatures in existence which is so unanimously hated, and hunted to death, as this poor obscure race of reptiles. It matters not that Homer has sung of their exploits, that Aristophanes has embellished them with his wit, that their history is one of the most wonderful on record,- -nothing avails to overcome the settled antipathy of mankind; and the Batrachians will probably go on to the end of their days maltreated and maligned, an unoffending but cruelly persecuted race.

It generally happens, that injustice of this sort, brings about its own punishment, and this is certainly the case in reference to the hard measure so undeservedly meted out to the Batrachians. The world looks down upon them, gives them ill names, affects a sort of horror of them, and does its best to kick them out of sight; and the consequence is that the world knows next to nothing about them, and thus misses one of the most marvellous chapters in the whole range of zoological science. The Batrachiophobia is at length giving way in one direction, it is true, for the aquarium has made it manifest that the waternewts, spite of a long cherished belief to the contrary, are perfectly harmless little creatures, elegant withal in their appearance, and very engaging in their behaviour. If prejudice did not stand in the way, we should be ready to admit that others of the order were equally deserving of our attention, and that horrid' and 'odious' as they

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are generally voted, it would be well worth the while of the curious in such matters to inquire into the details of their habits and economy. We propose then, to put in a plea on behalf of the frog and his friends, and to show cause why the entire fraternity of Batrachians should henceforth be dealt with in a more humane and considerate fashion. It will be no difficult task to accomplish, nor will it involve us in anything like a dull and disagreeable discourse; for however repugnant it may be to the notions prevalent on this side the English Channel to introduce any of these little fellows upon the dinner-table, there can be no question as to the excellence of the literary piece de résistance they furnish, if only it be concocted with a little artistic discrimination and care. Our readers will be good enough perhaps to make trial of the dish for themselves. They will find in it nothing that can offend the most fastidious palate, and if they only have the courage to go through with it, we shall have no misgivings as to the nature of their verdict. The Batra chians have rarely, if ever, had a word said in their behalf in our popular literature, and yet we confidently affirm that in connexion with no other branch of natural history is it possible to obtain more really 'good entertainment.'

It may be as well, perhaps, to begin our discourse by informing such as are disposed to look down upon the Batrachians, that, in the estimation of some of the first naturalists of the day, these animals are entitled to a considerably higher rank than that to which they are generally supposed to belong. The common idea of course is that they are neither more nor less than reptiles, the entire group being regarded as one of the orders' or principal divisions of that class of animals. The opinion, however, is now very generally entertained that they ought properly to be regarded as constituting by themselves a distinct class, equal in relative importance to each of the other great classes of the animal world, and occupying an intermediate position between the true reptiles and the inferior class of fishes. If this view of the matter be allowed, our little friend the frog and his allies

will part company with their quondam associates of the reptile tribes, the snakes, the lizards, and the tortoises, and, raised to a higher level, will take their place, on terms of equality, with the other great divisions of the vertebrate animals. The Batrachians themselves are no doubt sublimely indifferent as to which way the decision may go on this very grave question, and would be but little elated, it may be presumed, should their elevation to the dignity of an independent class be ultimately agreed to by a unanimous vote of all the zoological professors of Christendom. But, for all that, the question is not without its interest to the student of nature, and as, totally irrespective of their own feelings on the subject, the Batrachians do really stand as candidates for this elevated post, they ought certainly to be regarded with becoming deference and respect.

There is another side to this question, however, which not only requires to be looked at, but is of prime importance. Whatever may be the true style and title of the Batrachianswhether they continue to be regarded as a subordinate group of the reptile class, or be raised to a class by themselves-one thing is quite certain, namely, that they do differ very materially from ordinary reptiles, and approximate in many particulars to the class of fishes. The group, as a whole, forms a clear and unmistakable transition from the one class to the other, affording one of the most beautiful illustrations of the truth of the old maxim, nihil per saltum, that can anywhere be found in the whole range of the animal world. In the lower divisions of the order or class, if class it is to be, we meet with creatures so completely fish-like in character that they can be separated from the fishes only by fixing on some point of distinction, which is purely arbitrary in its nature; and from these questionable forms we advance, step by step, to the higher divisions, the members of which make a close approach to the character of true reptiles. Nor is it in one particular merely that this gradual advance from a lower to a higher grade of being is seen. It is noticeable alike in almost every separate feature of the organization, and

chiefly in those which are of the greatest importance in the economy of animal life. It is obvious, therefore, that the Batrachians form a strictly intermediate and transitionary group; and so completely do they bridge over the difference between the fishes adapted for a purely aquatic life, and the true air-breathing land reptiles, that they obliterate, so to speak, all essential distinction between them. It was in allusion to this fact that Professor Owen stated a short time since, in one of his public lectures, that, strictly speaking, there are neither fish nor reptiles, the two classes so denominated really forming one indivisible series of cold-blooded vertebrate animals.

If there be any one thing which, more than another, shows the true character of the Batrachians, it is the remarkable changes they undergo in the early period of their history. The transformation of a tadpole into a frog exhibits, in the successive phases of the life of an individual animal, substantially the same stages of advancement towards a higher type of organization, as are marked by the mature forms of the several members of the group as a whole. It will be interesting, therefore, to notice by what steps this progressive improvement of structure is made; and, as there is no lack of tadpoles in our ponds and ditches throughout the spring and early part of summer, any of our readers who choose to do so, may readily verify our statements for themselves.

The illustrious Knickerbocker begins his history of New York with an account of the creation of the world, alleging, what is highly probable, that if the world had never been created, New York would never have been built. On the same principle, we feel it necessary, in narrating the transformation of the tadpole, to begin with a reference to the parent frog; for the probability is very great indeed, that, if there were no frogs in the autumn, there would be no tadpoles to be seen in the following spring. In the beginning of March, then, the frogs which, all the winter through, have been comfortably conglobulated' together, as Dr. Johnson said of the swallows, in the mud at

the bottom of the ponds and ditches, wake up from their protracted sleep, and make their appearance at the surface of the water. In a little while they are all busily engaged in their nuptial rites, with respect to which, the only remark we have to make is, that we wish they were somewhat less obtrusively thrust upon our notice. The eggs are deposited in large masses at the bottom of the water; but as each egg is surrounded by a covering of glutinous matter, which readily absorbs water, the entire mass speedily swells, and becoming lighter than the surrounding medium, it rises to the surface. In this stage the eggs appear as little black dots, separated from each other by a transparent colourless jelly; and it is only by bearing in mind the extraordinary abundance in which this spawn is to be seen in the water in spring, that one can account for the myriads of tiny frogs to be found hopping about the margins of the ponds later in the year. For about a month or five weeks the eggs gradually increase in size; at the end of that period the young frogs-as yet far otherwise than frogs, however, in form-burst the envelopes of the eggs, eat their way through the gelatinous walls that imprison them, and make their escape into the water.

Having hatched our eggs, let us now watch attentively the subsequent changes of the frog progeny. In the condition in which the little creature commences its active life, it is known to every village urchin in the land as the tadpole, or loggerhead. The Cockney school-boys give it the more expressive name of tiddler. The little thing seems all head and tail. 'It is provided,' says Cuvier, with a long fleshy tail, and a small horny beak, and has no other apparent members but little fringes at the sides of the neck.' These fringes are the tadpole's breathing organs, and one of the earliest changes it experiences is the shrinking of these organs, and their subsequent disappearance beneath the skin, where they discharge the functions of the gills of a fish. The mouth of the tadpole is placed low down in the front of the head, so that when the little fellow wishes to seize anything floating on the surface of the water, he has to throw himself on his

back like a shark, and so nimbly does he execute this manoeuvre, that the eye cannot without difficulty follow it. Thus expert in appropriating food, the tadpole rapidly increases in size, the tail acquires greater breadth, and the limbs slowly make their appearance. The hind feet are developed first, increasing by little and little, and then the fore feet also appear. The beak now falls off, and exposes the true jaws, which were before soft and concealed under the skin: the tail is gradually reabsorbed, and the young frog begins to assume something like his mature form. In a few days more the little fellow, advanced to the dignity of positive froghood, takes his leave of the water, and steps ashore, thenceforth repudiating the shrivelled remnant of his once ample tail, which is now speedily disposed of after the manner in which Lord Monboddo, and the author of the Vestiges, would have us believe that our own quadrumanous progenitors disposed of theirs.

Thus much for what is external and obvious to the most cursory inspection in the transformation of the tadpole. But while these external changes are in progress, modifications of still more importance are taking place in the whole of the internal organization. The examination of the details of these modifications is not, perhaps, the most entertaining part of our subject, using that word entertaining in its ordinary acceptation; but to those who care to look into the matter, and to note how much that is really wonderful there is in the most common and familiar objects, few investigations can afford greater inter

est.

In the first place, let us look at the development of the spinal column or back-bone. In the newly-hatched tadpole this part of the structure consists of little more than a simple fibro-cartilaginous cord. As the little creature grows, this cord begins to ossify, though only in that portion which is to be retained in the future frog. After the process of ossification has gone on for a short time, the fibro-cartilaginous cord becomes converted into a distinct vertebral column; both faces of the separate vertebræ, however, are concave, and between

each pair of vertebræ there is precisely the same sort of hollow, filled with fluid, as that which distinguishes the vertebral column of fishes. But ossification proceeds; and now gradually filling up the hinder cavity of each vertebra, and projecting the newly-formed bone into the front cavity of the vertebra behind, it finally converts the entire series into a vertebral column, connected throughout by the true ball-and-socket joint characteristic of the higher reptiles. The changes which take place in the circulatory and breathing apparatus are not a whit less remarkable. In the first instance, the condition of these organs is, in all essential particulars, precisely the same as in the class of fishes. Thus the blood, driven from the arterial bulb through the branchial arteries, circulates freely through the gills, and is again collected in the branchial veins, which unite towards the back in a single external trunk. The pulmonary arteries first make their appearance in a very rudimentary form, springing from the branchial vessels. But as the lungs are developed and aërial respiration commences, the pulmonary arteries rapidly increase in size, the branchia and their vessels meanwhile gradually diminishing. The change still proceeding, the branches which unite the branchial arteries acquire a much greater development, and gradually divert more and more of the blood from the branchiæ, which now speedily disappear altogether, and leave to the pulmonary arteries the task of carrying on the entire business of respiration. In this way the little fish-like tadpole, adapted exclusively for an aquatic life, gradually becomes metamorphosed into a being possessing every requisite for a strictly terrestrial existence; though, whether it be from the strength of early associations, or from some more recondite cause, the frog seldom wanders far from his original home; and appears, his life through, to prefer to either land or water, strictly so called, that convenient compromise between the two afforded by the swamp or ditch.

The progressive changes related above, are understood, of course, to obtain only in the young of the higher grade of Batrachians. In the

lower forms, the metamorphosis is arrested at various points, so that the mature condition of these animals marks, so to speak, the successive stages in the development of the young of the more advanced members of the order. But there are some rather curious, and some truly extraordinary circumstances in connexion with the early history of some of these higher members, which must be referred to here. In the first place, there is a toad, common enough throughout the Continent, and well known in the neighbourhood of Paris, which has obtained for itself the name of the Accoucheur Toad (Bufo obstetricans), from the singular habit of the male assisting the female in the exclusion of the eggs, which he afterwards attaches to his own hind-legs, and carries about with him till the young tadpoles are ready to escape, when he conveys his charge to the water, where henceforward the young make their way in the world just as tadpoles that are less highly favoured with parental care. Still more extraordinary is the procedure of the monstrous Surinam toad. The eggs of this species are deposited by the female at the margin of the water, and are then carefully collected by the male and deposited upon the back of his partner, where a number of singular pits or cells exhibit themselves. A single egg is pressed by the male toad into each of these cells, which are then closed with a sort of lid. The development of the tadpole proceeds, in these confined spaces, in exactly the same way as with those of the other Batrachia which roam at large in the water; and when the young animal has completed its changes, it comes forth at once a perfect toad. In the salamanders, again, the early part of the development of the young takes place within the body of the parent. It is not a little singular, too, that in the conversion of the bi-concave into cupand-ball vertebræ, in the development of the tadpole of the salamander, the newly-formed bone fills up and extends from the front cavity, so that in the adult vertebræ the ball is anterior, and the cup posterior, as in some of the more reptile-like fishes. The waternewt, instead of depositing its eggs in patches or masses like the frog, or in

long chains like the common toad, doubles them in singly in the leaves of aquatic plants. In the young newts, again, the development of the forelegs precedes that of the hind pair, while, as we have already stated, the reverse of this takes place in the young frog, which, by the way, appears from observations communicated to Mr. Patterson of Belfast, to be in the habit of literally putting its left leg foremost,' the left fore-limb being perfectly developed, while the other is still nowhere.'

Mr. Bell, in his History of British Reptiles, brings a serious charge against the tadpole of the frog, accusing it of no less a crime than downright cannibalism; and, what is not a little odd in the matter, is, that the horrible propensity only manifests itself on the appearance of the limbs in any of the tadpole's companions. Suspecting that this was the case, Mr. Bell placed in a large glass globe of water several tadpoles nearly approaching their final change, and he observed that, almost as soon as one of them acquired its limbs, it would be found dead at the bottom of the water, and the other tadpoles feeding upon it. This took place with all of them successively, excepting the last, which not being able, or perhaps disposed, to eat himself, lived to complete his change, and doubtless grew fat upon the ruin of his fellows. We must not close our record of these various incidents and exceptions in the transformation of the tadpole, without presenting our readers with the account of the matter given by that prince of fabulists, Pliny. The passage is but brief, and the reader shall have it in the good old English version of Philemon Holland :- 'That which is ingendred and brought forth (by frogs), is as it were some little mites of blackish flesh, which they call Tadpoles, or Polwigs, shewing no good form, but that they haue some shew of eies only, and a taile. Some few daies after, their feet are framed, and then parts their taile in twain, which serueth for their feet behind. And a strange thing it is of them: after they haue liued some six months, they resolue into a slime or mud, no man seeth how: and afterward with the first rains in the Spring, returne again to their former state, as they