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The following particulars of the infancy and maturity of the common frog, are extremely curious.
'The batracians proceed from eggs which have a membraneous envelope, and which must remain in the water before the young can be excluded. The animal which proceeds from this egg has the form and structure of a fish. It has no feet, and its body is terminated by a very long and compressed tail formed like a fin; it is then named a tadpole. On this subject it is indispensable that we should enlarge a little on the observations of the text.
The tadpole then is a young batracian, from the moment in which it issues from the egg, until, after various metamorphoses, it passes to the adult state, without preserving either its form, structure, or even its mode of living.
When we examine the different periods of its evolution in the eggs of frogs, (which of all the eggs of reptiles have been the most carefully studied, as to the development of germs) we find that during the three or four days which follow the fecundation, the tadpole is nothing but a kidney-formed mass of small granulations. Towards the middle of the fourth day, these little grains are confounded one with the other: the embryo becomes distinct. It is divided by a contraction into two parts, one of which comprehends the head and thorax, the other the abdomen and tail. It is immersed in a fluid, which Swammerdam has compared to that of the amnios.
Moreover, according to the same observer, we then perceive in the eggs in question, an allantois, a chorion, an amnios, and umbilical vessels.
During the fifth day, the embryo increases a little, and towards the evening of the sixth, we see besides the head, thorax, abdomen and tail, a gill appear on each side of the neck, and answer the purpose of respiration, for the little animal, of swimming, and reposing itself in the glairy fluid.
In the course of the seventh, and at the commencement of the eighth day, the fœtus successively leave the albuminous fluid of the milt; and from thence until the thirteenth day they exhibit no change of form, and merely augment in volume.
'On coming out of the egg the little batracian is blind and without feet. It has a tail even in the anourous species of frogs and toads; it respires by gills; it has a large and globulous belly; its intestines are excessively long. It lives solely on vegetable substances, with the exception, according to M. Dumeril, of the obstetric toad.
This is the state in which it is named by us tadpole, a word which literally signifies the young of a toad. The French call it tetard, from tete, (head,) in consequence of the volume of the anterior part of the body. At this time it inhabits the water as a matter of necessity.
But it soon changes its skin; its eyes begin to shew themselves. First its two hinder feet, then the fore-feet appear on the sides of the trunk, and finally, the fall of the tail is speedily followed by the loss of the gills, while at the same time the digestive canal looses much of its dimensions. Then the animal respires the atmostpheric air, and acquires the form which it is destined to preserve for the rest of its existence.'- pp. 415-417.
As materials of human nutriment, frogs have been occasionally employed. Whether or not the Romans used them as food, we have no authority for deciding. In modern Europe they have been considered as a great luxury at our tables. All parts of these reptiles, except the skin and entrails, are commonly eaten in Germany, whilst in France the hinder quarters, we believe, are the only portions that it is considered proper or useful to dress.
After a description of the anatomical peculiarities of the salamander, Mr. Griffith furnishes the following details with respect to its habits.
'It takes up its abode in the humid earth, in the tufted woods of high mountains, in ditches and shady places, under stones and the roots of trees, in hedges, by the banks of streams, in subterraneous caverns, and ruined buildings. Though generally feared, it is by no means dangerous. The milky fluid which exudes from its skin, and which it sometimes shoots to the distance of several inches, though nauseous, acrid, and, according to Gesner, even depilatory, is fatal only to very small animals. This humour, however, doubtless was the cause of a general proscription of the salamander. According to Pliny, by infecting with its poison all the vegetables of a vast extent of territory, this reptile could produce death to entire nations.
It is almost unnecessary to repeat now, that there is not the slightest foundation for the story of this animal being able to resist the action of fire.
'If the salamander be struck, it raises its tail, and seems affected by catalepsy. It seldom quits the hole where it makes its habitual residence. It passes its life in general under ground. During summer, it dreads the heat of the sun, and seldom ventures forth, except in rainy seasons, or by night. Its walk is slow and heavy. It is stupid, and totally destitute of courage, never braving danger, as has been pretended. It is true, indeed, that it does not seem to perceive the approach of peril, against which it advances blindly, without deviating from its route; but this is mere stupidity, not courage.
It lives on flies, worms, young snails, scarabei, earth-worms, &c. It also eats humus.
Though very tenacious of life, it falls rapidly into convulsions, if it be steeped in vinegar, or sprinkled with salt.
The perceptive powers of this reptile seem to be remarkably dull. It shows no dread of the presence of man, or of animals stronger than itself. Other animals, however, seem to have an instinctive horror of it. Its bite is perfectly harmless, though Matthioli has declared it to be equally mortal with that of the viper-an atrocious absurdity.
The salamander utters no cry. On being thrown into the water, it tries immediately to get out again, and comes every moment to the surface to respire. When on the ground, it frequently rolls itself into a spiral.
It appears, according to the authority of Gesner, that in countries too much elevated in latitude, the salamanders pass the winter in a sort of burrow under ground, where numbers of them are to be found, assembled, and intertwisted together.
The salamander, like the viper, is oviparous. The eggs open in the
oviducts, and the young come forth fully formed. The latter, whose tail is compressed vertically, are folded in two, to the number of from eight to twenty in the five oviducts, where they are nourished by a peculiar fluid, and from which they do not come until they have gone through all their metamorphoses, that is, have lost their gills, and acquired their feet. Then they are deposited near marshes, to the number of forty, and even sometimes fifty at a time. Their colour is an uniform black.'-pp. 471—
This description respects the terrestrial salamander, there being also the aquatic salamander, which differs in its conformation from the first only in having a form of tail that is better calculated for an inhabitant of the waters.
Such is the nature of the interesting phenomena, whose intelligible and eloquent description, occupies the pages of these volumes. To the comparative anatomist they afford the indispensable materials for the pursuit of his particular department of study-but to the enthusiastic worshipper of nature, they must prove invaluable, as embracing not merely the details of the most interesting branches of natural science, in the best attested and most authentic form, but as explaining those details in a manner the best calculated to win the mind over to the contemplation of such objects, and to stimulate it to a closer and more extended investigation of their details.
We should be guilty of great injustice if we did not allude to the numerous plates which adorn the work, and which, representing in several instances new species, and, we believe, in all cases being immediate copies from nature, bear the impress of the most refined degree of art.
ART. VIII.-Memoir of the Life, Writings, and Correspondence of James Currie, M.D., F.R.Š., of Liverpool, Fellow of the Royal College of Physicians, Edinburgh, London Medical Society, &c. &c. Edited by his Son, William Wallace Currie. In two volumes. 8vo. London: Longman, Rees, and Co. 1831.
THE life of such a man as Dr. Currie, the sphere of whose usefulness was contracted not less by the circumstances in which he was placed during his life, than by the moderate share of talents which he possessed, can never be held up to the contemplation of men for any more exalted purpose than as the exemplary one of a good citizen. He cannot, indeed, be allowed to belong to that order of superior beings whose memories are borne to the remotest ends of the human community, by the practical benefits which they derived from his genius and exertions. Still it is enough of eulogy for Dr. Currie to say that he made one of that permanent confederacy of useful men, who by their silent, but persevering endeavours, from time to time, are so peculiarly instrumental in bringing about those sure, although tedious, ameliorations, which constitute so many brilliant epochs in the progress of society.
Dr. Currie was born at the manse of Kirkpartrick-Fleming, in Annandale, Scotland, on the 31st of May, 1756. At an early age, partaking of the spirit of enterprize that spread itself at the time amongst his countrymen, he embarked for North America, in a mercantile employment. Here he remained until the era of the commencement of that glorious revolt which terminated in the independence of the United States, when he found it necessary to return to his own country. He devoted himself to the medical profession, and in process of time, aspired to the appointment of physician to a military expedition which was about to sail for Jamaica. On his journey to the metropolis, we are told that he visited Dumfriesshire, where he met with an encounter, of which we find the following description in his journal.
'One Sunday evening in the summer of the year 1780, being on a visit to Sir William Maxwell, I was tempted by the fineness of the weather to take a solitary walk. The evening was still, the whole country was silent, and the calmness and serenity of the surrounding objects diffused a pleasing tranquillity over my mind. Leaving the house, I bent my steps towards the Kirtle, whose waters were beautifully irradiated by the beams of the setting sun; and advancing up along its banks in deep meditation, I was insensibly led into the bosom of a thick forest. Pursuing my course, I was struck with the appearance of a churchyard surrounded by very lofty elms, inhabited by a flock of rooks, whose cawing interrupted at times the solitary stillness of the scene. On examination, I could discover the ruins of a church, long gone to decay. After wandering some time among the tomb-stones, I entered a small chapel, by a flight of stairs, which I found was built over the burial-place of the family of Springkell. I had just light enough to discover the family escutcheon, which hung on the walls. As I returned towards the door, I heard a very uncommon noise; and when I got to the top of the stairs, I saw a human figure sitting between two graves, covered almost over with long grass, and bending its eye upon me with an expression of countenance that had in it nothing earthly. The complete silence and solitude of the place the solemnity of the surrounding objects, heightened by the gloom of evening,-conspired with the sudden appearance of the spectre to shake my nerves in every fibre. I stood gazing with astonishment and terror; when this apparition, suddenly springing up with a hideous laugh, assumed the form of a woman half naked, and, bounding lightly over the graves, was soon hid in the surrounding wood. My heart sank with dismay, and it was several minutes before I could recover my recollection. I retraced my way with hurried steps along the river-the fearful vision still present to my imagination-and arrived, breathless and terrified, at the mansion of Springkell. Here I soon discovered that the cause of my affright was a poor unhappy maniac, known by the name of Susanna, who ranged through the country uncontrolled, and was known to take up her nightly residence in the neighbouring woods."-vol. 1. pp. 53-54.
Being disappointed in procuring the expected situation, Currie proceeded from London to Liverpool, which town he resolved on making his permanent residence. Here he appears to have been
very successful, both in medicine and literature, and as a natural consequence of this improvement in his circumstances, he took to himself a wife, in the person of a Miss Wallace, who, though born in Ireland, is with a very legitimate pride of pedigree, represented to be a descendant of the immortal Scotsman of that name. To his honour, Dr. Currie vindicated, with becoming zeal, the abolition of the slave-trade; and his sincerity in advocating the cause of humanity on the occasion will readily be admitted, when it is remembered, that by adopting this course, he placed himself in immediate opposition to the leading men in Liverpool, on whose favourable opinion depended in a great measure his professional success. Dr. Currie maintained with the venerable Roscoe, during his life, a most affectionate degree of intimacy. They were even more than once associated in the same literary labour, and were equally, for a time, the objects of curiosity to the strangers who visited Liverpool, and had time to go in quest of its lions. The Doctor took also a most active part in seconding the efforts of the Dissenters, who endeavoured in 1790, to remove the obnoxious Test and Corporation Laws, the disgrace of which we have only so recently seen obliterated. In 1793, Dr. Currie published a pamphlet, containing two letters, signed Jasper Wilson, against the prolongation of the war with France. This work produced a great sensation, and was universally read-but perhaps the best criterion of its success was, the alarm which it produced in the government, and which prompted them to take measures for counteracting, if possible, the force of its reasoning on public opinion.
'A pamphlet so remarkable was the object of various replies; no less than five.. none of which were much read; for the rapid succession of the events prophesied by Jasper Wilson confuted his antagonists before they could be reasoned with. Of these answers, the most popular, composed in the manner and spirit of a gentleman, was that of Mr. Vansittart (now Lord Bexley), who, it was stated at the time, was summoned from the country for the purpose of writing it. If superior, as it was considered to be, in the commercial argument, it may be fairly pronounced to fall far behind in the discussion of the general question. At length, in February, 1794, came out an answer by Mr. George Chalmers, chief clerk of the office of Trade and Plantations, of which Lord Hawkesbury (afterwards Earl of Liverpool) was President, in the form of a dedication to a new edition of the author's "Estimate of the comparative Strength of Great Britain; " which was in tone, offensively course and vulgar, and in manner, impertinently and unwarrantably familiar. The Letter of Jasper Wilson was, in itself, strictly constitutional and decorous, both in language and in spirit. While it deprecated the war, it breathed what the author sincerely felt-an ardent attachment to his country, and veneration for the British constitution. Here, then, it was invulnerable, however fallacious its reasonings, or misdirected its object, might be thought. But the plan pursued by Mr. Chalmers tended to deprive it of this advantage. Not satisfied with unceremoniously, and without previous notice, addressing his dedication to Dr. Currie by name, as the author of Jasper