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tion, entertains grave doubts on this subject." For our own part, governed by the motto of the parent society for the promotion of natural knowledge, “nullius in verba," our attention was principally directed, in the first perusal of Mr. Darwin's work, to the direct observations of nature which seemed to be novel and original, and to the additional grounds, based on fact, on which a more lasting superstructure of the theory of the mutability of species might be raised. These observations, therefore, claim our notice before we proceed to discuss the general theory of the work.

No naturalist has devoted more painstaking attention to the structure of the barnacles than Mr. Darwin. In reference to the transitions of organs, and the probability of their conversion from one function to another, he states:

"fourteen nests of that species and found a few
slaves in all. Males and fertile females of the
their proper communities, and have never been
slave species (Formca fusca) are found only in
observed in the nests of F. sanguinea. The
slaves are black, and not above half the size of
their red masters, so that the contrast in their
appearance is very great. When the nest is
slightly disturbed, the slaves occasionally come
out, and, like their masters, are much agitated
and defend the nest: when the nest is much dis-
turbed and the larvæ and pups are exposed, the
carrying them away to a place of safety. Hence,
slaves work energetically with their masters in
it is clear, that the slaves feel quite at home.
During the months of June and July, on three
successive years, I have watched for
many hours
saw a slave either leave or enter a nest. Dur-
several nests in Surrey and Sussex, and never
ing the present year, however, in the month of
July (1859), I came across a community with
an unusually large stock of slaves, and I ob-
leaving the nest, and marching along the same
served a few slaves mingled with their masters
road to a tall Scotch fir-tree, twenty-five yards
distant, which they ascended together, probably
in search of aphides or cocci. According to
Huber, who had ample opportunities for obser-
vation, in Switzerland, the slaves habitually
work with their masters in making the nest, and
they alone open and close the doors in the morn-

"Pedunculated cirripedes have two minute folds of skin, called by me the ovigerous frena, which serve, through the means of a sticky secretion, to retain the eggs until they are hatched within the sack. These cirripedes have no branchia, the whole surface of the body and sack, including the small frena, serving for res-ing and evening; and, as Huber expressly states, piration. The Balanidæ or sessile cirripedes, on the other hand, have no ovigerous frena, the eggs lying loose at the bottom of the sack, in the well-enclosed shell; but they have large folded branchiæ. Now I think no one will dispute that the ovigerous frena in the one family are strictly homologous with the branchia of the other family; indeed, they graduate into each other."-P. 191.

That is, a series of modifications are affirmed to have been met with in different species, changing a respiratory into an ovigerous organ. Should this graduation of parts be confirmed, and the respiratory function of the folded membranes in Balanidæ be determined, Mr. Darwin will have contributed both an interesting observation, and a valuable discovery. But neither in the present work, nor in the two volumes published and illustrated at the cost of the Ray Society, are those relations of the folded membranes in the Balanidae with the heart or vascular system demonstrated, which could alone prove the respiratory function of such

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their principal office is to search for aphides.
Another day my attention was struck by about
a score of the slave-makers haunting the same
spot, and evidently not in search of food; they
approached and were vigorously repulsed by an
independent community of the slave species (F.
fusca); sometimes as many as three of these
ants clinging to the legs of the slave-making F
sanguinea. The latter ruthlessly killed their
as food to their nest, twenty-nine yards distant;
small opponents, and carried their dead bodies
but they were prevented from getting any pupa
to rear as slaves. I then dug up a small parcel
of the
pup of F. fusca from another nest, and
put them down on a bare spot near the place
of combat; they were eagerly seized, and car-
ried off by the tyrants, who perhaps fancied that,
after all, they had been victorious in their late
combat."-P. 221.

Many other direct observations on the F. sanguinea of England are recounted, and are contrasted with those first recorded by Huber, relative to the slave-holding F. rufescens of Switzerland.

"Such are the facts, though they did not need confirmation by me in regard to the wonderful instinct of making slaves. Let it be observed what a contrast the instinctive habits of F. sanguinea present with those of the F. rufescens. The latter does not build its own nest, does not determine its own migrations, does not collect food for itself or its young, and cannot even feed itself it is absolutely dependent on its numer ous slaves. F. sanguinea, on the other hand, possesses much fewer slaves, and in the early

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part of the summer extremely few. The masters | absolutely impossible, from the extreme thinness
determine when and where a new nest shall be of the little rhombic plate, that they could have
formed, and when they migrate the masters effected this by gnawing away the convex side;
carry the slaves. Both in Switzerland and Eng-and I suspect that the bees in such cases stand
land the slaves seem to have the exclusive care in the opposed cells and push and bend the duc-
of the larvae, and the masters alone go on slave-tile and warm wax (which, as I have tried, is
making expeditions. In Switzerland the slaves easily done) into its proper intermediate plane,
and masters work together, making and bring-and thus flatten it.
ing materials for the nest: both, but chiefly the "From the experiment of the ridge of ver-
slaves, tend, and milk, as it may be called, their million wax, we can clearly see that if the bees
aphides; and thus both collect food for the were to build for themselves a thin wall of wax,
community. In England the masters alone they could make their cells of the proper shape,
usually leave the nest to collect building ma- by standing at the proper distance from cach
terials and food for themselves, their slaves, and other, by excavating at the same rate, and by
larvæ. So that the masters in this country re-endeavoring to make equal spherical hollows,
ceive much less service from their slaves than
they do in Switzerland."-P. 223.

but never allowing the spheres to break into each other."-P. 230.

The instincts of the bee have received not Mr. Darwin, while collecting objects of less attention from Mr. Darwin than those natural history in the rivers of Brazil, was of the ant; and he has also enriched this surprised at the similarity of the fresh-water interesting part of natural history by new insects, shells, etc., and at the dissimilarity and original remarks.* Desirous of testing of the surrounding terrestrial beings, comthe mechanical hypothesis of the formation pared with the fauna of Great Britain, and of the hexagonal cell, out of an original cy-he was led to ponder on this power, as it lindrical form, by pressure of surrounding cylinders, Mr. Darwin

seemed, in fresh-water productions, of ranging widely. He offers many ingenious suggestions to account for the phenomena, and gives, what is of greater value, the following original observation and experiment:

separated two combs, and put between them a long, thick, square (rectangular?) 'strip of wax; the bees instantly began to excavate minute circular pits in it; and as they deepened these little "Two facts which I have observed-and no pits they made them wider and wider until they doubt many others remain to be observed-throw were converted into shallow basins, appearing to some light on this subject. When a duck sudthe eye perfectly true or parts of a sphere, and denly emerges from a pond covered with duckof about the diameter of a cell. It was most weed, I have twice seen these little plants adherinteresting to me to observe that wherever several ing to its back; and it has happened to me in bees had begun to excavate these basins near removing a little duckweed from one aquarium together, they had begun their work at such a to another, that I have quite unintentionally distance from each other, that by the time the stocked the one with fresh-water shells from the basins had acquired the above stated width (i.e.other. But another agency is perhaps more about the width of an ordinary cell), and were effectual: I suspended a duck's feet, which might in depth about one-sixth of the diameter of the represent those of a bird sleeping in a natural sphere of which they formed a part, the rims of pond, in an aquarium, where many ova of freshthe basins intersected or broke into each other. water shells were hatching; and I found that As soon as this occurred, the bees ceased to ex-numbers of the extremely minute and just cavate, and began to build up flat walls of wax on the lines of intersection between the basins, so that each hexagonal prism was built upon the festooned edge of a smooth basin, instead of on the straight edges of a three-sided pyramid as in the case of ordinary cells."-P. 228.

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With regard to the mechanical origin of the bee's cell, Mr. Darwin proceeds to say :"In one well-marked instance, I put the comb back into the hive, and allowed the bees to go on working for a short time, and again examined the cell, and I found that the rhombic plate had been completed, and had become perfecily flat; it was

*In the remarkable volume recently published by Lord Brougham, entitled "Tracts, Mathematical and Physical," which have been produced by his lordship at various times from the year 1796 to the year 1858, will be found an excellent paper on the mathematical structure of bees' cells, read before the National Institute of France, by Lord Brougham, in the French language, in May, 1858. It is a scientific and literary curiosity.

hatched shells crawled on the feet, and clung to them so firmly that when taken out of the water they could not be jarred off, though at a somewhat more advanced age they would voluntarily drop off. These just-hatched molluscs, though aquatic in their nature, survived on the duck's feet, in damp air, from twelve to twenty hours; and in this length of time a duck or heron might fly at least six or seven hundred miles, and would be sure to alight on a pool or rivulet, if blown across sea to an oceanic island or to any other distant point."-P. 385.

birds may serve to transmit species of aquatic
The mud adhering to the feet of wading
plants far away from their native streams.

"I do not believe (writes Mr. Darwin) that
botanists are aware how charged the mud of
ponds is with seeds. I have tried several little
experiments, but will here give only the most
striking case. I took, in February, three table-
spoonfuls of mud from three different points
beneath the water, on the edge of a little pond.

could hardly be detected in the young. But there was one remarkable exception to this rule, for the young of the short-faced tumbler differed from the young of the wild rock-pigeon and of the other breeds, in all its proportions, almost exactly as much as in the adult state." - P. 445.

This mud, when dry, weighed only six and were incomparably less than in the full-grown three-fourths ounces. I kept it covered up in birds. Some characteristic points of difference my study for six months, pulling up and count--for instance, that of the width of mouthing each plant as it grew. The plants were of many kinds, and were altogether five hundred and thirty-seven in number; and yet the viscid mud was all contained in a breakfast cup! Considering these facts, I think it would be an inexplicable circumstance if water-birds did not transport the seeds of fresh-water plants to vast distances, and if consequently the range of these plants was not very great. The same agency may have come into play with the eggs of some of the smaller fresh-water animals."P. 386.

These are the most important original observations, recorded in the volume of 1859: they are, in our estimation, its real gems, few indeed and far apart, and leaving the determination of the origin of species Facing the difficulty of the transport of very nearly where the author found it; but fresh-water or land shell-fish across long a rich mine of such researches is alluded to tracts of ocean, on the supposition of a trans- and promised by Mr. Darwin, in a more porting bird occasionally resting on, or dip-voluminous collection of his researches, exping in, the salt sea, or in the case of such shells adhering to drifted timber, Mr. Darwin made more experiments, and found

"That several species did in this state withstand uninjured an immersion in sea-water during seven days: one of these shells was the Helix pomatia, and after it had again hybernated I put it in sea-water for twenty days, and it perfectly recovered. As this species has a thick calcareous operculum, I removed it, and when it had formed a new membranous one, I immersed it for fourteen days in sea-water, and it recovered and crawled away."-P. 397.

tending over a period of eighteen years; and to these every naturalist now looks forward with keen interest.

The interdependencies of living beings of different kinds and grades, and the injurious results of their interruption, have long attracted the attention of observant and philosophic naturalists. An undue importance indeed was at one time attached to this principle; it was deemed to be so absolute as that no one species could be permitted to perish without endangering the whole fabric of organization. So Pope sang :—

Tenth or ten thousandth, breaks the chain alike."

Pigeons being monogamous, and prover-« From Nature's chain, whatever link you strike, bial for their constancy, are peculiarly favorable for experiments and practices establishing and propagating varieties. Such varieties consequently have become, under the selective care of man, numerous and extreme. Believing it to be best, in reference to the question of the origin of varieties, to study some special group, Mr. Darwin took up domestic pigeons, associated himself with several eminent pigcon-fanciers, and joined two of the London Pigeon Clubs. He gives descriptions of the leading varieties: and amongst his own observations, the following, perhaps, conveys the newest matter:—

Manifold subsequent experience has led to a truer appreciation and a more moderate estimate of the importance of the dependence of one living being upon another. Mr. Darwin contributes some striking and ingenious instances of the way in which the principle partially affects the chain, or rather net-work of life, even to the total obliteration of certain meshes. And truly, extinction has made wide rents in the reticulation as now represented by the co-affinities of living species!

"As the evidence appears to me conclusive, "From experiments which I have tried, I that the several domestic breeds of pigeon have have found that the visits of bees, if not indescended from one wild species, the Rock-dispensable, are at least highly beneficial to the pigeon (Columba livia), -I compared young fertilization of our clovers; but humble-bees pigeons of various breeds, within twelve hours alone visit the common red clover (Trifolium after being hatched; I carefully measured the Pratense), as other bees cannot reach the nectar. proportions (but will not here give details) of Hence I have very little doubt, that if the whole the beak, width of mouth, length of nostril and genus of humble-bees became extinct or very of cyclid, size of feet and length of leg, in the rare in England, the heartscase and red clover wild stock, in pouters, fantails, runts, barbs, would become very rare, or wholly disappear. dragons, carriers, and tumblers. Now some of The number of humble-bees in any district dethese birds, when mature, differ so extraordina-pends in a great degree on the number of fieldrily in length and form of beak, that they would, I cannot doubt, be ranked in distinct genera, had they been natural productions. But when the nestling birds of these several breeds were placed in a row, though most of them could be distinguished from each other, yet their proportional differences in the above specified several points

mice, which destroy their combs and nests; and Mr. H. Newman, who has long attended to the habits of humble-bees, believes that more than two-thirds of them are thus destroyed all over England.' Now the number of mice is largely dependent, as every one knows, on the number of cats; and Mr. Newman says, 'Near villages

full-grown difference mouthEng. Bat

this rule, r differed On and of 5, almost

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and small towns I have found the nests of hum- not the whole, of the original observations ble-bees more numerous than elsewhere, which adduced by its author in the volume now I attribute to the number of cats that destroy the before us, our disappointment may be conmice.' Hence it is quite credible that the pres-ceived. Failing the adequacy of such obence of a feline animal in large numbers in a dis-servations, not merely to carry conviction, trict might determine, through the intervention but to give a color to the hypothesis, we were first of mice and then of bees, the frequency then left to confide in the superior grasp of

of certain flowers in that district!"-P. 73.

mind, strength of intellect, clearness and precision of thought and expression, which might raise one man so far above his contemporaries, as to enable him to discern in the common stock of facts, of coincidences, correlations and analogies in Natural History, deeper and truer conclusions than his fellowlaborers had been able to reach.

These expectations, we must confess, received a check on perusing the first sentence in the book.

This is very characteristic of the ingenious turn of thought of our author; the more sober, or perhaps duller, naturalist would, no doubt, appreciate more highly a dry statement of investigations, suggested by the actual extinction of red clover, and tracing that extinction inductively, by the ascertained absence of humble-bees and mice, back to the want of cats in the neighborhood. For the direct observation, however (if it should be confirmed), of the exclusive re"When on board H.M.S. 'Beagle,' as naturlation of Bombus terrestris, as the mechanical alist, I was much struck with certain facts in the fecundator of Trifolium pratense, natural distribution of the inhabitants of South Amerhistory may be indebted to Mr. Darwin. ica, and in the geological relations of the present We wish we could cite other instances aug-to the past inhabitants of that continent. These menting this debt from the present work; its facts seemed to me to throw some light on the chief part, however, is devoted to specula- origin of species-that mystery of mysteries, as tions on the origin of species; and its main it has been called by some of our greatest phiobject is the advocacy of a view which we losophers."-P. 1. find most clearly expressed in the following passage. Mr. Darwin refers to the multitude of the individuals of every species, which, from one cause or another, perish either before, or soon after attaining maturity.

What is there, we asked ourselves, as we closed the volume to ponder on this paragraph, what can there possibly be in the inhabitants, we suppose he means aboriginal inhabitants of South America, or in their distribution on that continent, to have suggested to any mind that man might be a transmuted ape, or to throw any light on the origin of the human or other species? Mr. Darwin must be aware of what is commonly understood by an "uninhabited island;" he may, however, mean by the inhabitants of South America, not the human kind only, whether aboriginal or otherwise, but all the lower animals. Yet again, why are the freshwater polypes or sponges to be called "inmore than the plants? Perhaps what was meant might be, that the distribution and geological relations of the organized beings generally in South America, had suggested transmutational views. They have commonly suggested ideas as to the independent origin of such localized kinds of plants and animals. But what the "certain facts" were, and what may be the nature of the light which they threw upon the mysterious beginning of species, is not mentioned or further alluded to in the present work.

Owing to this struggle for life, any variation, however slight and from whatever cause proceeding, if it be in any degree profitable to an individual of any species, in its infinitely complex relations to other organic beings and to external nature, will tend to the preservation of that individual, and will generally be inherited by its offspring. The offspring, also, will thus have a better chance of surviving, for, of the many individuals of any species which are periodically born, but a small number can survive. I have called this principle, by which each slight variation, if useful, is preserved, by the term of Natural Selection, in order to mark its relation to man's power of selection. We have seen that man by selection can certainly produce great results, and can adapt organic beings to his own uses, through the accumulation of slight but useful variations, given to him by the hand of Nature. But Natural Selection, as we shall hereafter see, is a power incessantly ready for action, and is as immeasurably superior to man's feeble efforts, as the works of Nature are to

those of Art."-P. 61.

habitants

The scientific world has looked forward
The origin of species is the question of
with great
interest to the facts which Mr. questions in zoology; the supreme problem
Darwin might finally deem adequate to the which the most untiring of our original la-
support of his theory on this supreme ques- borers, the clearest zoological thinkers, and
tion in biology, and to the course of induc- the most successful generalizers, have never
tive original research which might issue in lost sight of, whilst they have approached it
throwing light on "that mystery of mys- with due reverence. We have a right to ex-
teries." But having now cited the chief, if pect that the mind proposing to treat of, and

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