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are both more frequent, and blow steadily up a continuous slope from the sea, while the latter are little felt near the lower ground, the ridge of the hill serving as a shelter, the result is an unmistakeable advance inland, and farms, houses, and even villages, become gradually obliterated. Much grass, of that peculiar kind that roots in loose sand, has been allowed to grow, but it is quite insufficient to check the evil.”

We must not, however, dwell longer on the scenic attractions of the Channel Islands, our object being to notice, in connection with the work whose title is appended to this paper, some of those features which possess special interest for the naturalist. We have been fortunate enough to have spent two very delightful summer holidays in investigating several branches of their natural history, and can cordially recommend any brother naturalist to whom the islands are unknown, to go and do likewise. Whatever branch of science occupies his attention, he may be pretty sure of finding abundant material for study. The islands are, moreover, very easy of access, and the expense of living, though not so exceptionally small, as in the good old times, when tourists were few and far between, is, at any rate, very much less than at most sea-side resorts.

It is interesting to note that the most picturesque and characteristic scenery of the Channel Islands-the caverns, detached pinnacles, and "creux," are at once the result and the evidence of a constantly progressive destruction. Professor Ansted thus sums up the conditions under which these results are produced :

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"Nowhere on our shores is the tidal wave so powerful, nowhere are the storm waves so frequent; nowhere is there a coast consisting of material in which so much rock of extreme hardness is penetrated so thoroughly with veins of softer material. The very hardness of the granite, where it is hard, produces an unusual destruction of the softer veins; for, as already explained, every fragment removed becomes a hammer, helping to undermine what is left. Whenever one hard mass is thrown down and broken up, another is soon attacked; and thus a perpetual and rapid destruction is caused, increasing constantly in area, and not diminishing in intensity."

This destruction goes on so rapidly as materially to alter the rock surfaces in a very short lapse of time; and it is certain that in historic times the general aspect and contour of the islands must have undergone very material change. Nor is this the only actively destructive agent. Earthquakes have been frequently felt, and even so lately as 1843 and 1853 shocks so violent as to cause great alarm have occurred.

The tides in the Channel Islands are the perplexity of dredgers, and add much by their violence and variable direction to the dangers of the coast. On this account, indeed, it is quite unsafe to venture on dredging or any other kind of boating without the help of experienced sailors. In many places the rush of the tide is tremendous. Through the narrow channel, for instance, between Sark and the Gouliot Rock, it sets with the impetuosity of a great river in flood; and we well remember that in passing through with a fresh breeze and all sail set, it was all our boat could do to make head against the stream. A most beautiful and accurate view of this spot is given by Mr. Naftel at page 81. The complicated character of the tides will be understood from the following remarks :

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"The course of the tidal wave through the waters that surround the Channel Islands may be thus stated. The great wave coming in from the Atlantic advances from the south-west, and is turned to the east. A part of it passes on to the north-east, north of the islands; but a part enters among them by various channels, and being first lifted by shoal water, and then thrown back by the coast of Normandy, it is both detained in its course, and is deflected to the north. At Mont St. Michel the magnitude of the wave is at its maximum. Owing to the vast extent of the shallow water, and the narrowness of the deeper passages throughout the great bay enclosing the islands, the wave remains extremely large, amounting in Jersey to nearly forty feet, in Guernsey to almost thirty. . . . The velocity of the tidal current, where not increased by narrow passages, is from two and a-half to three miles per hour. Although the course of the tidal wave may be thus traced, the current by no means follows the same law. In this respect the complication is so great that it would be quite impossible to describe it in this place; but, in a general way, it may be stated that the stream does not flow northwards with the advancing tide wave in the open channels till the wave has been flowing three hours, and that when it has turned it continues in that direction not only till the flood has turned, but till the retiring wave has receded half its course. In other words, the stream flows from half flood to half ebb, and ebbs from half ebb to half flood. While, however, this is the case in certain channels, the direction of the stream is not only different, but often diametrically opposite, at no great distance, but somewhat nearer shore."*

A visitor to Guernsey cannot fail to be struck with the great luxuriance of vegetation, especially of exotic forms. Plants which in England we are accustomed to regard as delicate or half-hardy, there thrive wonderfully, without any extraordinary care being bestowed upon them, even in winter. Hydrangeas and fuschias are particularly abundant, adorning almost every cottage garden with masses of bloom, which would be the pride of many an English conservatory. Fuschias attain the height of fifteen or twenty feet, and are rather trees than shrubs. The splendid Mexican aloe, Agave Americana, grows freely, sending up its gorgeous flower-stalks thirty or forty feet high. Yuccas, the Camellia japonica, and numerous exotic bulbous plants flourish in the open air. The well-known Guernsey lily is an example of the latter class; and, says Professor Ansted, "the great beauty of the rich red flower of this lily, and the fact that it flowers regularly once in two or three years in the island, while it can seldom be made to flower a second time in England, are subjects of great pride to the islanders." Nor is this richness of vegetation confined to cultivated plants the indigenous flora affords many illustrations of the great geniality of the climate. Fronds of the sea, spleenwort (Asplenium marinum), have been gathered three feet in length; and in every lane

"Between Guernsey and the Casquets the current sets from every point of the compass during each advance and recession of the tidal wave; hence the navigation is exceedingly difficult and dangerous in foggy weather, ships being sometimes drifted miles out of their course."

+In the South Isles of Arran, Galway Bay, we have gathered fronds of this plant of a similar size, and Adiantum capillus veneris nearly as large. The two ferns grew together in perpendicular rock fissures on the beach, and, whatever the depth of the fissure, they sent up their fronds to the level, or

some of the commoner ferns, such as Asplenium adiantum-nigrum, and Scolopendrium vulgare, are to be found growing in the greatest luxuriance. Guernsey exhibits this richness of vegetation in a much greater degree than any of the other islands; the reason being that its more seaward situation brings it more decidedly under the warming influence of the gulf stream, at the same time removing it further from the disturbing influence which the proximity of a great continent must to some extent produce. The tables of temperature given in the work before us exhibit very clearly the remarkable equability of climate enjoyed by the Channel Islands, and by Guernsey more particularly. For details we must refer the reader to the work itself; but the following table will show at a glance sufficient reason for this remarkable luxuriance of vegetation :—

Greenwich.

46.9°

60.6°

49.9°

38.2°

Mean temperature of

Spring months (March, April, May)
Summer months (June, July, August)
Autumn months (Sept., Oct., Nov.)
Winter months (Dec., Jan., Feb.)

Guernsey.

17.7°

59.9°

53.8°

44.2°

The lists of the flora and fauna given by Mr. Ansted, though the work of many able hands, are confessedly incomplete, excepting those of the flowering plants and ferns, which are all based upon Mr. Babington's "Primitia Floræ Sarnica." The catalogue of seaweeds includes two hundred and twenty-two species,-an extensive list, the whole number of recorded British species being about three hundred and ninety. The islet of Herm is not represented in this list, and from our own gatherings there we can add the following species :—Callithamnion floridulum (very abundant), Cladophora diffusa, and C. gracilis, Elachistea pulvinata and E. scutulata, Leathesia tuberiformis, Melobesia calcarea, M. lichenoides, &c., Mesogloia virescens, and several others. It is worthy of notice, however, that the red algæ in Herm are mostly very poor in colour, owing to the deficiency of shelter from sunlight: they are more frequently yellow or green than red, except on the east coast, where the rocks offer more shade. The lists of Crustacea, both stalk-eyed and sessile-eyed, are also very imperfect. Amongst the former, for example, of the genus Pagurus, only two species are given in addition to these we may name P. lævis, Hyndmanni, cuanensis, and ferruginens. But, notwithstanding unavoidable imperfections of this kind, the lists are very valuable as an attempt to illustrate thoroughly the botany and zoology of the islands, and will form an admirable nucleus around which the discoveries of other observers may be gathered.

We have already noticed the peculiarities of the Channel Island scenery, and have not space for more than the following short extract,

nearly to the level, of the surrounding rock. A more favourable condition for fern growth it is impossible to conceive; the successive growth and decay of the leaves producing a constantly accumulating rich and loose soil, while the sides of the rock crevices afforded abundant shelter,

descriptive of the celebrated Gouliot Caverns in Sark, which may well be called the El Dorado of the British naturalists :

"The first cavern is of noble proportions, and the floor is roughly piled with immense boulders, giving many and varied views of the small but picturesque Havre Gosselin,' seen through the opening at the further extremity. But this cavern, though fine, is, as it were, a mere outer court, preparing us for the glories to be revealed within. Its walls are partly covered with those singular currant-jelly-like animals one sees expanded like living flowers in marine aquaria; deep blood-red is the prevailing colour, but dark olive-green varieties are also common, and numerous yellow and brick-red patches are seen at intervals. A few mussels and tens of thousands of limpets and barnacles cover the boulders. Abundance of life is seen, and some of the specimens are as rare as they are beautiful. A branch of the first cavern, in which is a deep pool of water, conducts to the sea; but it is better to wait till low water and creep round outside. We then enter a gloomy series of vaults, lighted from the sea, and communicating with each other by natural passages. Every square inch of the surface is covered with living zoophytes; and in some parts an infinite number of Tubularia are seen occupying the walls."

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The work from which we have extracted is edited jointly by Messrs. Ansted and Latham, the former having contributed the sections embracing Natural History and Physical Geography, as well as the Economics and Trade of the Islands; the latter being author of the chapters on Civil History and Antiquities. That the whole has been admirably performed cannot admit of doubt. The volume is beautifully printed, and contains numerous illustrations of scenery by Mr. P. J. Naftel. These are most artistically executed, and are faithful as well as pictorial: we know no other engravings which so agreeably reproduce the character of the Channel Island scenery.

THE ORIGIN OF SPECIES.*

(MR. DARWIN AND HIS COMMENTATORS.)

HE minds of men are so variously constituted that the observation of one and the same phenomenon often produces upon different individuals totally distinct and opposite impressions.

THE

As in the tale of the travellers and the chameleon, one person examines an object from one position, and declares it to be white; another views it from a different stand-point, and unhesitatingly affirms that it is black; whilst a third, approaching it from the quarter where the two effects neutralize one another, pronounces it to be both, or neither, and at length discovers that it is grey; and he at once proceeds to enlighten the disputants.

*Professor Huxley's Lectures to Working Men on "Our Knowledge of the Causes of the Phenomena of Organic Nature." R. Hardwicke.

Are we correct (we would inquire of the thoughtful reader), when we say that the debated controversy of the "Origin of Species" has assumed somewhat of this aspect to one who belongs to neither rank of controversialists?

Leaving out of consideration a host of writers, who have dealt with the subject without understanding anything of its merits, or who have formed hasty or prejudiced conclusions in regard to it, we still find many illustrious names rendered still more prominent by their association with that greatest of all nature's problems-the creation, modification, and continued existence of living forms; and where the leading naturalists of the age are found to hold diametrically opposite views, we can take but little credit to ourselves for having exercised caution in the expression of our own opinions.

But those who have followed us in our labours will be aware that we have done more than to exercise self-control; we have often (no doubt to the dissatisfaction of our correspondents) toned down, or entirely expunged statements which assumed as undeniable facts what many unprejudiced observers still regard as not proven, or even reject as error; and this we have done in order that a hasty expression of opinion on the one side might not call forth an acrimonious retort from the other.

The result has been that these pages are the neutral ground upon which men and women holding every phase of theological and political belief have met without restraint, and have learned to respect one another as searchers after truth. And it is chiefly with a view to maintain this prestige that we now venture to approach a question which will not allow itself to be cast aside; and upon which it is, therefore, right that each and all of us should bring our best judgment to bear.

During the brief period of the existence of this Periodical, we have had occasion to notice three works bearing upon the subject of the "Past and Present Conditions of Organic Nature ;"* all written by authors whose names are more or less intimately associated with the controversy; and now there lies before us a fourth treatise, an unpretending little volume, so far as outward appearance goes, and comprising only 157 small widely printed pages of matter. But this little work, diminutive though it be in its proportions, contains the deliberately expressed convictions of a naturalist who is invested with great authority by virtue of his official appointments in the educational departments of the State; and whose careful and untiring research gives weight to any opinions that he may think fit to express in public on those subjects which (to confine ourselves for the present to an expression of his own) tend to "the improvement of man's estate, and the widening of his knowledge."

66

"The Past and Present Life of the Globe." By D. Page. Blackwood. (No. 1, Popular Science Review.") "Unité de l'Espèce Humaine" (Unity of the Human Species). By De Quatrefages. Hachette, Paris. (No. 2, "Popular Science Review.") "On the Fertilisation of Orchids." By Charles Darwin, author of the "Origin of Species." Murray. (No. 5," Popular Science Review.")

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