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person has thought of the affinity!" Now, with such an admission, and in the face of a declaration of Baron Cuvier, that the cepha lopoda differ entirely in their organization from the vertebrata, quant au plan et à l'arrangement général, tant interieur qu'ex térieur,' nothing but the most hopeless despondency could have induced an advocate of the quinarian system to unite his contigu ous circles of vertebrata and mollusca, by a vinculum so slender and unsuitable.-Has the attempt to unite the vertebrata with the annulosa been more successful?

The transition from the vertebral to the annulose animals is conceived to take place from the lamprey, among fishes, to the leech, in the annelides. Both animals have red blood, swim with an undulatory motion, have a circulation by veins and arteries, breathe by branchial pouches, and have the mouth formed to act as a sucker, with teeth in the interior. At first sight, these apparent affinities seem to justify the relation sought to be established; but are they fit to stand the test even of a moderate scrutiny? In reference to the nervous system, there is no relation either of affinity or analogy between the two species. The organs of sight in the lamprey and neighbouring genera are constructed according to the ordinary plan of the eyes of fishes; while in the leech, there are no organs with which the former can be compared, unless the ten black points on the margin of the upper lip, which were detected by Professor Carena, may be denominated eyes. The lamprey has organs of hearing and smelling, together with a tongue; of all which the leech is destitute. The lamprey has a sucker, with which it can adhere to its prey, and numerous teeth, wherewith to detach portions for food, to be swallowed by the aid of the tongue, and to enter a gullet, stomach, and intestine, and be ejected by the vent in the middle of the belly, as in other fishes the leech has likewise a sucker and three teeth, with the last of which a wound is made in the skin; the blood, in the absence of a tongue, enters the alimentary canal, which, after a series of constrictions, but in the absence of liver or kidneys, proceeds to the posterior extremity, where the vent opens above the tail. In the lamprey, there is a heart, well protected, with a regular circulation:-in the leech, there is no heart, and though there be a longitudinal vessel on each side, considered as arteries, and one along the belly and another along the back, regarded as veins, M. Thomas has seen the blood in these pretended arteries moving sometimes in one direction and sometimes in another. In the lamprey, the organs of respiration consist of pectinated gills, in pouches opening externally by lateral apertures, and internally by passages leading to the mouth, as in other chondropterygious fishes with fixed gills-in the leech, respiration is sup

posed

posed to take place by the intervention of vesicular bags, with minute external orifices along each side of the body, from one extremity to the other, unconnected internally with the mouth, and having simple walls. In the lamprey, the male and female organs. of generation appear, from the observations of Sir Everard Home, to be united in the same individuals, so as to render conjunction unnecessary; the eggs, when expelled, are naked, and each contains a single foetus in the leech, the hermaphroditism requires the union of two individuals; the eggs, when expelled, are covered with a spongy matter, and each contains several young. In the lamprey, progress is made through the water by a laterally undulating motion of the body :-in the leech, progress is made through the water by a vertically undulating motion, or, over hard substances, by a sucker on the tail, acting alternately with the one on the head, like the geometers among caterpillers. In the lamprey, rest is secured by the sucker at the mouth, the tail being free:

in the leech, rest is secured by the caudal sucker, the head being free, or by both suckers acting simultaneously. Such being the vast differences existing in the organization of the two animals, we may well be astonished that any individual who had ever made the comparison should have been able to perceive very evident affinities,' where there existed only a few very remote and insignificant analogies. Nor need we hesitate to conclude that the hiatus between the vertebrata and annulosa is as great as that acknowledged to exist between the former and the mollusca. These defects in the system occur in those parts of the circle which are best kuown, and where the organization of the species is least obscure. In connecting the other circles, defects equally remarkable and extensive might be pointed out, were it necessary to enlarge; for whenever a relation of affinity is wanting, analogical resemblances are eagerly sought after, and incautiously employed; the judgment is deceived; and the imagination, unchecked, rears an edifice, which the breath of truth may destroy in

a moment.

In the course of the efforts which have been made to establish the quinarian system, we have witnessed a classification of animals, founded on the characters of their circulating and respiring organs, sacrificed, with scarcely the shadow of apology, to hypothetical views. The division of animals into vertebral and invertebral, founded on considerations connected with the nervous system, has likewise been rejected, because it does not state Denough; and that the young naturalist, placing full reliance on hit, may be led to conceive that animals have been formed on only two distinct plans,' This statement, however, exhibits a very inaccurate view of the subject: for, while the vertebral group is

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declared as formed on a plan (and this no one will deny), the invertebral group is distinguished only by the negative mark, being destitute of a vertebral column, and concomitant characters. Nay, so much convinced is the author of the Hora Entomologica' of the existence of only two plans in the animal kingdom, that he acknowledges that the vertebrata are the perfection of one plan of organization, as the annulosa may be of another.' From thus overlooking the dichotomous method, on the one hand, as the only natural guide to discrimination, primary groups occupy the same station with such as are of subordinate rank; the logical genus is confounded with species, the major with the minor proposition: while, from disregarding the physiological groups or systems of organs, on the other hand, as the index of affinities, one set of organs are employed to establish a connection here, another to accomplish the same object there; confounding together analogy and affinity in that very system which calls most loudly for their separation. Under such a mode of management may the circles selected be so connected, by some one of the various organs, as always to exhibit a relationship; and even, if their juxtaposition be altered, they may still display new bonds of connection, leading the author of the quinarian circle to exclaim, with him of the tripod, stabit quocunque jeceris.'

If we abandon the principle by which subordination of rank among our groups is preserved, and attempt, by the exclusion of all negative characters, to have each of our classes or circles founded on some positive feature of organization, then will our primary groups be co-extensive with our genera. By limiting the primary groups to five, the quinarians thus abandon, in some measure, their own principles; and the same means which they employ to divide a group when a fifth is wanting, might enable them to subdivide others to the destruction, however, of the harmony of their system. What, but the most obvious prejudices in favour of hypothetical views, could induce Mr. Macleay to divide insecta into mandibulata and haustellata, and leave entire the arachnida? Of this system, indeed, it has been well said by one of the most distinguished naturalists of the age- Mr. Macleay's whole system, upon paper, appears very harmonious and consistent, and bears a most seducing aspect of verisimilitude; but it has not yet been so thoroughly weighed, discussed, and sifted, as to justify our adopting it in toto at present.' Enough, we trust, has been advanced, in the preceding observations, to prove that its weakness is most apparent where its triumphs should have been the greatest, and that its author, while indulging the dream of being supported by evident affinities,' was in fact relying on very deceitful analogies,

The

The advocates for the existence of the law of continuity' among created beings in their mutual relations, have experienced no small degree of pain from those chasms which so frequently present themselves, and which prove so destructive to their speculations, as they occur, in equal abundance, among the best known groups as in those of most difficult investigation. They have attempted to train Nature to walk over a course, which they have marked out, with an equal pace. But, greatly to their annoyance, she occasionally makes a halt-as when she refused retractile claws to the hunting tiger; indulges in frolicsome leaps, as in passing from the vertebral to the invertebral animals;-and completes the confusion of those who wish to train her, by bolting off the course, to convey Man to his rational throne.

They have endeavoured to soothe their feelings by imagining that the unexplored regions of the globe may yet yield forms calculated to supply present deficiencies, and connect the detached links of the linear or circular chain. Much, no doubt, remains to be done in the discovery of species, and, perhaps, still more in comprehending the structure, functions, and distribution of those which systems have already recognised; but the boldest advocate of this scheme has not even ventured to hope for the discovery of a semirational species to fill up the greatest gap which exists. Some misgivings seem to prevail even with respect to this supposed fertility of unknown regions. These naturalists have therefore ventured to call upon the hills and mountains to give up the organic remains which they possess, in order to furnish forms and structures calculated to connect anomalous groups, inclose aberrant genera, and give harmony and continuity to the system. Geology, however, in all its bearings, opposes the bold requisition. The strata present to the student the relics of various groups of organized beings; but these must be examined in the peculiar compartments which have been allotted to them. The fossils of the chalk rocks must not be mingled with those of the carboniferous limestone, nor with the species which now exist. All these must be studied as separate systems-the works of the same Omnipotent Creator-formed for particular purposes, and existing during different epochs

' of the capacious plan Which heaven spreads wide before the view of man.'

ART.

ART. III.-History of Scotland. By Patrick Fraser Tytler, Esq., F.R.S.E. and F.A.S. Volumes 1 and 2. 8vo. Edinburgh, 1829.

IN N our last Number, we made some remarks on the history of the northern part of this island during those ages in which the light dawns slowly as the sunrise on a morning of mist The present author has adopted for the subject of his work a period of somewhat later than that at which we left off, and thus escapes the dim and doubtful discussion over which our heads have ached," and our readers' eyes have perhaps slumbered. Feeling our own c optics a little too much dazzled by passing at once from the darki ness of Kenneth Mac Alpine's period into the comparative full, light of Alexander the Third's reign, we shall introduce our readers more gently to the latter era; nor can we do so without expressing our hope that Mr. Tytler may find time, before completing his projected labours, to furnish us with some preliminary! matter in the shape of introduction, or otherwise, so as to inform his readers of what royal race Alexander sprung, and over what people he reigned.

On this point it is singular to discover that the Scots, whose Fabulous history represented them, down to the end of the eighteenth century, as a nation of the purest blood and most ancient descent in Europe, can, notwithstanding that vaunt, be easily traced as a mixed race, formed out of the collision and subsequent union of several different populations, which remained slightly connected or occasionally dissevered, till the difference in their manners was worn away by time, and they coalesced at length into one people and kingdom.

We have formerly shown that, in the year 496, a body of Irish, then called Scots, had colonised Argyllshire, and made fierce wars on the decaying province of Rome, by the assistance, doubtless, of those called Meatæ, or Middle Britons, who, subjected by the Romans during their power, rose against them when it began to decline. These Scots, moreover, made war upon the Caledo-l nians, more latterly called Northern Picts or Deucaledonians, who had for ages been in possession of the greater part of! Angusshire, Perthshire, Fife, and the north-east of Scotland up to the Moray firth. Beyond that estuary it would appear the Scandinavians had colonies upon the fertile shores of Moray, and among the mountains of Sutherland, of which the name speaks for itself that it was given by the Norwegians; and probably they had also settlements in Caithness and the Orcades. When, therefore, Kenneth finally defeated, dispersed, and destroyed the Piets, he obtained possession of the middle provinces of Scotland from>

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