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28%	F1357 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. London: John Murray. Text Image PDF ticles which they can swallow are left in it. They mingle the whole intimately together, like a gardener who prepares fine soil for his choicest plants. In this state it is well fitted to retain moisture and to absorb all soluble substances, as well as for the process of nitrification. The bones of dead animals, the harder parts of insects, the shells of land-molluscs, leaves, twigs, c., are before long all buried beneath the accumulated castings of worms, and are thus brought in a more or
28%	F1357 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. London: John Murray. Text Image PDF foot-stalks, unless the basal part of the blade is as narrow as the apex, or narrower than it. When we behold a wide, turf-covered expanse, we should remember that its smoothness, on which so much of its beauty depends, is mainly due to all the inequalities having been slowly levelled by worms. It is a marvellous reflection that the whole of the superficial mould over any such expanse has passed, and will again pass, every few years through the bodies of worms. The plough is one of the most
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF Park, where the ground beneath was bare of all vegetation, not a single casting could be found over wide spaces, even during the autumn. Nevertheless, castings were abundant on some grass-covered glades and indentations which penetrated this forest. On the mountains of North Wales and on the Alps, worms, as I have been informed, are in most places rare; and this may perhaps be due to the close proximity of the subjacent rocks, into which worms cannot burrow during the winter so as to escape
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF other hand he kept several large worms alive for nearly four months, completely submerged in water.* During the summer when the ground is dry, they penetrate to a considerable depth and cease to work, as they do during the winter when the ground is frozen. Worms are nocturnal in their habits, and at night may be seen crawling about in large numbers, but usually with their tails still inserted in their burrows. By the expansion of this part of their bodies, and with the help of the short
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF plainly marked with their tracks. I have noticed this from August to May, both months included, and it probably occurs during the two remaining months of the year when they are wet. On these occasions, very few dead worms could anywhere be seen. On January 31, 1881, after a long-continued and unusually severe frost with much snow, as soon as a thaw set in, the walks were marked with innumerable tracks. On one occasion, five tracks were counted crossing a space of only an inch square. They
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF pots in the house; so that by looking down into their burrows, their heads could just be seen. If the ejected earth or rubbish over the burrows be suddenly removed, the end of the worms body may very often be seen rapidly retreating. This habit of lying near the surface leads to their destruction to an immense extent. Every morning during certain seasons of the year, the thrushes and blackbirds on all the lawns throughout the country draw out of their holes an astonishing number of worms; and
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF to act perhaps once out of half a dozen trials. The light was on one occasion concentrated on a worm lying beneath water in a saucer, and it instantly withdrew into its burrow. In all cases the duration of the light, unless extremely feeble, made a great difference in the result; for worms left exposed before a paraffin lamp or a candle invariably retreated into their burrows within from five to fifteen minutes; and if in the evening the pots were illuminated before the worms had come out of
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF times a poker heated to dull redness near some worms, at a distance which caused a very sensible degree of warmth in my hand. One of them took no notice; a second withdrew into its burrow, but not quickly; the third and fourth much more quickly, and the fifth as quickly as possible. The light from a candle, concentrated by a lens and passing through a sheet of glass which would intercept most of the heat-rays, generally caused a much more rapid retreat than did the heated poker. Worms are
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF piano; and their sensitiveness to jars varied much at different times. It has often been said that if the ground is beaten or otherwise made to tremble, worms believe that they are pursued by a mole and leave their burrows. From one account that I have received, I have no doubt that they do so when pursued by moles; but a gentleman informs me that he lately saw eight or ten worms leaving their burrows and crawling about the grass on some boggy land on which two men had just trampled while
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF is certainly the case with worms. Cabbage-leaves are much liked by worms; and it appears that they can distinguish between different varieties; but this may perhaps be owing to differences in their texture. On eleven occasions pieces of the fresh leaves of a common green variety and of the red variety used for pickling were given them, and they preferred the green, the red being either wholly neglected or much less gnawed. On two other occasions, however, they seemed to prefer the red. Half
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF particles of sugar and liquorice; and the worms which I kept drew many bits of dry starch into their burrows, and a large bit had its angles well rounded by the fluid poured out of their mouths. But as they often drag particles of soft stone, such as of chalk, into their burrows, I feel some doubt whether the starch was used as food. Pieces of raw and roasted meat were fixed several times by long pins to the surface of the soil in my pots, and night after night the worms could be seen tugging at
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF From the secretion with which the leaves are moistened being alkaline, and from its acting both on the starch-granules and on the protoplasmic contents of the cells, we may infer that it resembles in nature not saliva,* but pancreatic secretion; and we know from Fr d ricq that a secretion of this kind is found in the intestines of worms. As the leaves which are dragged into the burrows are often dry and shrivelled, it is indispensable for their disintegration by the unarmed mouths of worms
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF of acids, which have been grouped together under the term of humus acids. We shall have to recur to this subject in our fifth chapter, and I need here only say that these acids act strongly on carbonate of lime. The half-decayed leaves which are swallowed in such large quantities by worms would, therefore, after they have been moistened and triturated in the alimentary canal, be apt to produce such acids. And in the case of several worms, the contents of the alimentary canal were found to be
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF digestive fluid. They cannot attack such strong leaves as those of sea-kale or large and thick leaves of ivy; though one of the latter after it had become rotten was reduced in parts to the state of a skeleton. Worms seize leaves and other objects, not only to serve as food, but for plugging up the mouths of their burrows; and this is one of their strongest instincts. They sometimes work so energetically that Mr. D. F. Simpson, who has a small walled garden where worms abound in Bayswater
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF question about food. A lady, who was interested in the habits of worms, removed the little heaps of stones from the mouths of several burrows and cleared the surface of the ground for some inches all round. She went out on the following night with a lantern, and saw the worms with their tails fixed in their burrows, dragging the stones inwards by the aid of their mouths, no doubt by suction. After two nights some of the holes had 8 or 9 small stones over them; after four nights one had about
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF during the night; but I have occasionally known objects to be drawn into the burrows during the day. What advantage the worms derive from plugging up the mouths of their burrows with leaves, c., or from piling stones over them, is doubtful. They do not act in this manner at the times when they eject much earth from their burrows; for their castings then serve to cover the mouths. When gardeners wish to kill worms on a lawn, it is necessary first to brush or rake away the castings from the
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF conceal the burrows from scolopendras, which, according to Hoffmeister,* are the bitterest enemies of worms, or from the large species of Carabus which attack them ferociously, for these animals are nocturnal, and the burrows are opened at night. May not worms when the mouth of the burrow is protected be able to remain with safety with their heads close to it, which we know that they like to do, but which costs so many of them their lives? Or may not the plugs check the free ingress, of the
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF undoubtedly instinctive with worms, yet instinct could not tell them how to act in the case of leaves about which their progenitors knew nothing. If, moreover, worms acted solely through instinct or an unvarying inherited impulse, they would draw all kinds of leaves into their burrows in the same manner. If they have no such definite instinct, we might expect that chance would determine whether the tip, base or middle was seized. If both these alternatives are excluded, intelligence alone is left; unless
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF son found 91 leaves which had been dragged by worms into their burrows, though not to a great depth; of these 66 per cent. had been drawn in by the base or foot-stalk; and 34 per cent. by the tip. In this case, therefore, the worms judged with a considerable degree of correctness how best to draw the withered leaves of this foreign plant into their burrows; notwithstanding that they had to depart from their usual habit of avoiding the foot-stalk. On the gravel-walks in my garden a very large
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF unknown motive. As already remarked, the habit of plugging up the mouths of the burrows with various objects, is no doubt instinctive in worms; and a very young one, born in one of my pots, dragged for some little distance a Scotch-fir leaf, one needle of which was as long and almost as thick as its own body. No species of pine is endemic in this part of England, it is therefore incredible that the proper manner of dragging pine-leaves into the burrows can be instinctive with our worms. But as
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF leaves had been left out during several nights, the tips of the needles of many leaves were tied together with fine thread. Of leaves thus treated 150 were drawn into burrows 123 by the base and 27 by the tied tips; so that between four and five times as many were drawn in by the base as by the tip. It is possible that the short cut-off ends of the thread with which they were tied, may have tempted the worms to drag in a larger proportional number by the tips than when cement was used. Of the
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF 5 had been previously drawn in by the base, for this part had been gnawed. Again, I collected a handful of petioles lying loose on the ground close to some plugged-up burrows, where the surface was thickly strewed with other petioles which apparently had never been touched by worms; and 14 out of 47 (i.e. nearly one-third), after having had their bases gnawed had been pushed out of the burrows and were now lying on the ground. From these several facts we may conclude that worms draw in some
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF see how the triangles would be seized by worms, some in a damp state were given to worms kept in confinement. They were seized in three different manners in the case of both the narrow and broad triangles: viz., by the margin; by one of the three angles, which was often completely engulfed in their mouths; and lastly, by suction applied to any part of the flat surface. If lines parallel to the base and an inch apart, are drawn across a triangle with the sides three inches in length, it will be
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF division far oftener than on either of the two other divisions. For the area of the basal to the apical part is as 5 to 1, so that the chance of the former being drawn into a burrow by suction, will be as 5 to 1, compared with the apical part. The base offers two angles and the apex only one, so that the former would have twice as good a chance (independently of the size of the angles) of being engulfed in a worms mouth, as would the apex. It should, however, be stated that the apical angle is
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF , being at the same time generally dirty. Of the 82 uncreased triangles, 14 were dirty at the base; but it does not follow from this fact that these had first been dragged towards the burrows by their bases; for the worms sometimes covered large portions of the triangles with slime, and these when dragged by the apexover the ground would be dirtied; and during rainy weather, the triangles were often dirtied over one whole side or over both sides. If the worms had dragged the triangles to the mouths
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF To sum up, as chance does not determine the manner in which objects are drawn into the burrows, and as the existence of specialized instincts for each particular case cannot be admitted, the first and most natural supposition is that worms try all methods until they at last succeed; but many appearances are opposed to such a supposition. One alternative alone is left, namely, that worms, although standing low in the scale of organization, possess some degree of intelligence. This will strike
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF passage by swallowing the earth; for it is incredible that the ground could yield on all sides to the pressure of the pharynx when pushed forwards within the worms body. That worms swallow a larger quantity of earth for the sake of extracting any nutritious matter which it may contain than for making their burrows, appears to me certain. But as this old belief has been doubted by so high an authority as Clapar de, evidence in its favour must be given in some detail. There is no priori
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF be seen every morning, and the amount of earth ejected from the same burrow on successive days is large. Yet worms do not burrow to a great depth, except when the weather is very dry or intensely cold. On my lawn the black vegetable mould or humus is only about 5 inches in thickness, and overlies lightcoloured or reddish clayey soil: now when castings are thrown up in the greatest profusion, only a small proportion are light coloured, and it is incredible that the worms should daily make fresh
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF another place at no great distance the castings were white; and why the worms should have burrowed into the chalk in some places and not in others, I am unable to conjecture. Two great piles of leaves had been left to decay in my grounds, and months after their removal, the bare surface, several yards in diameter, was so thickly covered during several months with castings that they formed an almost continuous layer; and the large number of worms which lived here must have subsisted during
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF out on all sides by the worm as it travels up or down its burrow. The lining thus formed becomes very compact and smooth when nearly dry, and closely fits the worm's body. The minute reflexed bristles which project in rows on all sides from the body, thus have excellent points of support; and the burrow is rendered well adapted for the rapid movement of the animal. The lining appears also to strengthen the walls, and perhaps saves the worm's body from being scratched. I think so because several
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF up, and does not appear to have been hitherto noticed. Many leaves of the Scotch-fir or pine (Pinus sylvestris) were given to worms kept in confinement in two pots; and when after several weeks the earth was carefully broken up, the upper parts of three oblique burrows were found surrounded for lengths of 7, 4, and 3 inches with pine-leaves, together with fragments of other leaves which had been given the worms as food. Glass beads and bits of tile, which had been strewed on the surface of the
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF as well as the seeds, are carried down from the surface by being swallowed; for a surprising number of glass beads, bits of tile and of glass were certainly thus carried down by worms kept in pots; but some may have been carried down within their mouths. The sole conjecture which I can form why worms line their winter-quarters with little stones and seeds, is to prevent their closely coiled-up bodies from coming into close contact with the surrounding cold soil; and such contact would perhaps
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF greater weight of the superincumbent soil which has to be raised, than in the parts near the surface. When the ground dries, the walls will shrink a little and the burrows will be a little enlarged. Their enlargement, however, through the lateral contraction of the ground, will not be favoured, but rather opposed, by the weight of the superincumbent soil. Distribution of Worms. Earth-worms are found in all parts of the world, and some of the genera have an enormous range.* They inhabit the most
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF three cubic centimeters. They were, therefore, of small size in comparison with those often found in England; for six large castings from a field near my house averaged 16 cubic centimeters. Several species of earth-worms are common in St. Catharina in South Brazil, and Fritz M ller informs me that in most parts of the forests and pasture-lands, the whole soil, to a depth of a quarter of a metre, looks as if it had passed repeatedly through the intestines of earth-worms, even where hardly any
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF of their having been found at 4 feet. Within the forests, fresh castings may be found even during the hot season. The worms in the Botanic garden, during the cool and dry season, draw many leaves and little sticks into the mouths of their burrows, like our English worms; but they rarely act in this manner during the rainy season. Mr. Scott saw worm-castings on the lofty mountains of Sikkim in North India. In South India Dr. King found in one place, on the plateau of the Nilgiris, at an
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF worms, the mould would hereafter be very slowly increased by their action. We will now give some cases of the action of worms, on land differing widely from the dry sandy or the swampy pastures just described. The chalk formation extends all round my house in Kent; and its surface, from having been exposed during an immense period to the dissolving action of rain-water, is extremely irregular, being abruptly festooned and penetrated by many deep well-like cavities.* During the dissolution of
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF found that it amounted, in the case of some worms which he kept in confinement, and which he appears to have fed with leaves, to only 0 5 gram, or less than 8 grains per diem. But a very much larger amount must be ejected by worms in their natural state, at the periods when they consume earth as food instead of leaves, and when they are making deep burrows. This is rendered almost certain by the following weights of the castings thrown up at the mouths of single burrows; the whole of which
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF part of the day by trees. It had been formed at least a century ago by a great accumulation of small and large fragments of sandstone, together with some sandy earth, rammed down level. It is probable that it was at first protected by being covered with turf. This terrace, judging from the number of castings on it, was rather unfavourable for the existence of worms, in comparison with the neighbouring fields and an upper terrace. It was indeed surprising that as many worms could live here as
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF England it must add to the mould on fields near great roads. But in our country these latter several agencies appear to be of quite subordinate importance in comparison with the action of worms. We have no means of judging how great a weight of earth a single full-sized worm ejects during a year. Hensen estimates that 53,767 worms exist in an acre of land; but this is founded on the number found in gardens, and he believes that only about half as many live in corn-fields. How many live in old
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF still at work. Knowing what great muscular power worms possess, and seeing how soft the concrete was in many parts, I was not surprised at its having been penetrated by their burrows; but it is a more surprising fact that the mortar between the rough stones of the thick walls, surrounding the rooms, was found by Mr. Farrer to have been penetrated by worms. On August 26th, that is, five days after the ruins had been exposed, he observed four [page] 18
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF 337 A.D. was found. My son William visited the place before the excavations were completed; and he informs me that most of the floors were at first covered with much rubbish and fallen stones, having their interstices completely filled up with mould, abounding, as the workmen said, with worms, above which there was mould without any stones. The whole mass was in most places from 3 to above 4 ft. in thickness. In one very large room the overlying earth was only 2 ft. 6 in. thick; and after this
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF As the foundations of the walls generally lie at a considerable depth, they will either have not subsided at all through the undermining action of worms, or they will have subsided much less than the floor. This latter result would follow from worms not often working deep down beneath the foundations; but more especially from the walls not yielding when penetrated by worms, whereas the successively formed burrows in a mass of earth, equal to one of the walls in depth and thickness, would have
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF hundred yards. * Nor should we forget, in considering the power which worms exert in triturating particles of rock, that there is good evidence that on each of acre of land, which is sufficiently damp and not too sandy, gravelly or rocky for worms to inhabit, a weight of more than ten tons of earth annually passes through their bodies and is brought to the surface. The result for a country of the size of Great Britain, within a period not very long in a geological sense, such as a million
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF beneath which many worm-castings were found. These had flowed bodily downwards, and others had rolled down as pellets. Hence it is certain that as long as a mound of this kind is tenanted by worms, its height will be continually lowered. The fine earth which flows or rolls down the sides of such a mound accumulates at its base in the form of a talus. A bed, even a very thin bed, of fine earth is eminently favourable for worms; so that a greater number of castings would tend to be ejected on a
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF ticles which they can swallow are left in it. They mingle the whole intimately together, like a gardener who prepares fine soil for his choicest plants. In this state it is well fitted to retain moisture and to absorb all soluble substances, as well as for the process of nitrification. The bones of dead animals, the harder parts of insects, the shells of landmolluscs, leaves, twigs, c., are before long all buried beneath the accumulated castings of worms, and are thus brought in a more or less
28%	F1361 Book: Darwin, C. R. 1881. The formation of vegetable mould, through the action of worms, with observations on their habits. fifth thousand (corrected), and with textual changes. London: John Murray. Text Image PDF foot-stalks, unless the basal part of the blade is as narrow as the apex, or narrower than it. When we behold a wide, turf-covered expanse, we should remember that its smoothness, on which so much of its beauty depends, is mainly due to all the inequalities having been slowly levelled by worms. It is a marvellous reflection that the whole of the superficial mould over any such expanse has passed, and will again pass, every few years through the bodies of worms. The plough is one of the most
28%	A1304 Review: Anon. 1881. [Review of Earthworms] Mr. Darwin on worms. Wallaroo Times and Mining Journal (South Australia), (3 December): 2. Text PDF world is swarming with worms; probably all over there are in every acre of land from 35,000 to 50,000 worms. Everyone is familiar with the casts of worms, which themselves look like worms of earth. With so many worms at work, then, it is not difficult to imagine what will be the effect of a constant accumulation of such casts. In some cases, if spread over the ground, they would measure, one fifth of an inch in depth per year, equal to 1 inch of earth brought up from below, passed through the
27%	A2964 Periodical contribution: [Dallas, W. S.] 1881. [Review of Earthworms]. Annals and Magazine of Natural History 5th ser. 8: 443-6. Text PDF justifies the following remarks of Mr. Darwin:—When we behold a wide turf-covered expanse, we should remember that its smoothness, on which so much of its beauty depends, is mainly due to all the inequalities having been slowly levelled by worms. It is a marvellous reflection that the whole of the superficial mould over any such expanse has passed, and will again pass, every few years through the bodies of worms. Large stones lying on the surface of grass-land become gradually imbedded, partly
27%	A2413 Review: Anon. 1881. [Review of Earthworms]. Sheffield Daily Telegraph (19 November): 11. Text PDF take in the formation of so-called vegetable mould, in the preservation of antiquities, and positively in altering the form of the surface of the earth; these facts are all the more surprising when we consider how comparatively low in the scale of animal life the earth-worms are, and how destitute they are of the organs and sense with which the higher animals are furnished. Worms, as is well known, have no limbs, and eyes and ears are also wanting; it appears, however, that they are not insensible
27%	A1294 Review: Anon. 1881. [Review of Earthworms] Mr. Darwin on worms. Annandale Observer and Advertiser (21 October): 4. Text PDF The Complete Work of Charles Darwin Online [page] 4 MR. DARWIN ON WORMS. MR. DARWIN'S new work, The Formation of Vegetable Mould through the Action of Worms, with Observations on their Habits, is devoted to a minute yet extremely interesting account of the anatomy and habits of the lowly earthworm, and the wonderful effects which its taste for eating dirt and voiding it again, acting through long ages, has produced on the surface of the earth. From this point of view the book has some slight

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