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F1364    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. Seventh thousand. Corrected by Francis Darwin. 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 this is often the case; but a gentleman informs me that he lately saw eight or ten worms leave their burrows and crawl about the grass on some boggy land on which two men had just trampled while setting a trap; and
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F1364    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. Seventh thousand. Corrected by Francis Darwin. London: John Murray.   Text   Image   PDF
L on Fredericq states* that the digestive fluid of worms is of the same nature as the pancreatic secretion of the higher animals; and this conclusion agrees perfectly with the kinds of food which worms consume. Pancreatic juice emulsifies fat, and we have just seen how greedily worms devour fat; it dissolves fibrin, and worms eat raw meat; it converts starch into grape-sugar with wonderful rapidity, and we shall presently show that the digestive fluid of worms acts on starch. But they live
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F1364    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. Seventh thousand. Corrected by Francis Darwin. London: John Murray.   Text   Image   PDF
ground beneath the old beech-trees in Knole Park, where worms appeared to be absent, was striking. A narrow path running across part of my lawn was paved in 1843 with small flag-stones, set edgeways; but worms threw up many castings and weeds grew thickly between them. During several years the path was weeded and swept; but ultimately the weeds and worms prevailed, and the gardener ceased to sweep, merely mowing off the weeds, as often as the lawn was mowed. The path soon became almost covered up
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F1364    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. Seventh thousand. Corrected by Francis Darwin. London: John Murray.   Text   Image   PDF
of the habits of worms, calculates, from the number which he found in a measured space, that there must exist 133,000 living worms in a hectare of land, or 53,767 in an acre. This latter number of worms would weigh 356 pounds, taking Hensen's standard of the weight of a single worm, namely, three grams. It should, however, be noted that this calculation is * Mr. R. Mallet remarks ('Quarterly Journal of Geolog. Soc,' vol. xxxiii., 1877, p. 745) that the extent to which the ground beneath the
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F1364    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. Seventh thousand. Corrected by Francis Darwin. London: John Murray.   Text   Image   PDF
summary 15 tons as the weight of the castings annually thrown up on an acre of land, each worm must annually eject 20 ounces. A full-sized casting at the mouth of a single burrow often exceeds, as we have seen, an ounce in weight; and it is probable that worms eject more than 20 full-sized castings during a year. If they eject annually more than 20 ounces, we may infer that the worms which live in an acre of pasture land must be less than 26,886 in number. Worms live chiefly in the superficial
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F1364    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. Seventh thousand. Corrected by Francis Darwin. London: John Murray.   Text   Image   PDF
places has certainly been accumulated by worms, yet it seemed hardly possible that this mould could have been brought up by worms from beneath the apparently sound floor. It seemed also extremely improbable that the thick walls, surrounding the room and still united to the concrete, had been undermined by worms, and had thus been caused to sink, being afterwards covered up by their castings. I therefore at first concluded that all the fine mould above the ruins had been washed down from the
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F1364    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. Seventh thousand. Corrected by Francis Darwin. London: John Murray.   Text   Image   PDF
CHAPTER V. THE ACTION OF WORMS IN THE DENUDATION OF THE LAND. Evidence of the amount of denudation which the land has undergone Sub-aerial denudation The deposition of dust Vegetable mould, its dark colour and fine texture largely due to the action of worms The disintegration of rocks by the humus-acids Similar acids apparently generated within the bodies of worms The action of these acids facilitated by the continued movement of the particles of earth A thick bed of mould checks the
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F1364    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. Seventh thousand. Corrected by Francis Darwin. London: John Murray.   Text   Image   PDF
Brading, castings from, with rounded particles, 257 Bridgman, Mr., on worms eating leaves of a Phlox, 34 Buckman on grasses profiting by being rolled, 10 Burial of the remains of ancient buildings by worms, 178 Burrows, depth of, 111 direction of, on a slope, 273 excavation of, 100 lined with black earth, 113 lined with leaves, 114 mouths of, worms lie motionless near, 15 old, their collapse, 120 plugged up, 60 terminating in a small chamber, often lined with stones or seeds, 116 Calciferous
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A2417    Review:     Anon. 1882. [Review of Earthworms]. North Wales Chronicle (7 January): 8.   Text
, almost unsuspected before, in producing the fertility of the soil. Instead of the vegetable mould being the origin of the worms which are everywhere to be found in it, it is in a great degree the product of these worms which make it and keep it fruitful
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
HABITS OF WORMS. CHAP. I. Fig.1. Diagram of the alimentary canal of an earth-worm (Lumbricus), copied from Ray Lankester in 'Quart. Journ. of Microscop. Sc.' vol. xv. N.S. pl. vii. latter organ is surrounded by weak longitudinal, but powerful transverse muscles. Perrier saw these muscles in energetic action; and, as he remarks, the trituration of the food must be chiefly effected by this organ, for worms possess no Jaws or teeth of any kind. Grains of sand and small stones, from the 1/20 to a
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
CONCLUSION. CHAP. VII. CHAPTER VII CONCLUSION. Summary of the part which worms have played in the history of the world—Their aid in the disintegration of rocks—In the denudation of the land—In the preservation of ancient remains —In the preparation of the soil for the growth of plants—Mental powers of worms—Conclusion. Worms have played a more important part in the history of the world than most persons would at first suppose. In almost all humid countries they are extraordinarily numerous
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F1364    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. Seventh thousand. Corrected by Francis Darwin. London: John Murray.   Text   Image   PDF
CHAPTER VII. CONCLUSION. Summary of the part which worms have played in the history of the world Their aid in the disintegration of rocks In the denudation of the land In the preservation of ancient remains In the preparation of the soil for the growth of plants Mental powers of worms Conclusion. WORMS have played a more important part in the history of the world than most persons would at first suppose. In almost all humid countries they are extraordinarily numerous, and for their size
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F1364    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. Seventh thousand. Corrected by Francis Darwin. London: John Murray.   Text   Image   PDF
Weight of earth ejected from a single burrow, 163 Whitaker, Mr., on Denudation, 234 White on worms leaving their burrows at night, 14 Winchester, chalk formation near, 304 Wind, action of, on castings, 286 Worms, nocturnal, 13 large numbers occasionally die, 14 dead eaten by other worms, 34 contents of intestines acid, 52 their castings acid, 58 power of suction, 58 plugging up their burrows, 60 intelligence of, 66 formation of their burrows, 100 number of, living in a given area, 161
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A2569    Review:     Anon. 1882. [Review of Earthworms]. Harper's New Monthly Magazine, 65 (June): 153-154.   Text   PDF
The Complete Work of Charles Darwin Online [page] 153 MORE than a hundred years ago that charming naturalist White of Selborne jotted down in a letter to his friend Daines Barrington some very curious and interesting facts concerning earth-worms, their uses and habits. Earth-worms, he wrote, though in appearance a small and despicable link in the chain of nature, yet, if lost, would make a lamentable chasm. For to say nothing of half the birds and some quadrupeds which are almost entirely
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
CHAP. IV. OF ANCIENT BUILDINGS. ing surface and thus afforded some shelter. The floors of the old rooms, halls and passages have generally sunk, partly from the settling of the ground, but chiefly from having been undermined by worms; and the sinking has commonly been greater in the middle than near the walls. The walls themselves, when-ever their foundations do not lie at a great depth, have been penetrated and undermined by worms, and have consequently subsided. The unequal subsidence thus
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F1364    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. Seventh thousand. Corrected by Francis Darwin. London: John Murray.   Text   Image   PDF
ing surface and thus afforded some shelter. The floors of the old rooms, halls and passages have generally sunk, partly from the settling of the ground, but chiefly from having been undermined by worms; and the sinking has commonly been greater in the middle than near the walls. The walls themselves, whenever their foundations do not lie at a great depth, have been penetrated and undermined by worms, and have consequently subsided. The unequal subsidence thus caused, probably explains the
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A1161    Review:     Anon. 1882. [Review of Earthworms] The formation of vegetable mould, through the action of worms: The earliest ploughman. The Youth's Companion, (20 April): 162.   Text   PDF
vegetable mould. The little piles left at the mouth of their holes are full of nutrition, and of the highest value for the growth of plants and vegetables. The worms fill an important place among agricultural laborers. The smoothness of beautiful lawns and meadows, Mr. Darwin says, is mainly due to all the inequalities having been slowly levelled by worms. The improvements which their industry effects are constant and progressive. The whole of the superficial mould over any expanse has passed, and will
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A2420    Review:     Anon. 1882. [Review of Earthworms]. "Darwin…choosing the things of God". Leavenworth Press (Kansas), 8, no. 240 (28 January): 2.   Text
The Complete Work of Charles Darwin Online [page] 2 Mr. Darwin's last book on The formation of vegetable mould through the action of worms, is a fine vindication of the religiousness both of science and scientists. Quietly and patiently Mr. Darwin holds on his way, choosing the lowly things of God to teach men an unerring lesson
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
THE FORMATION OF VEGETABLE MOULD, THROUGH THE ACTION OF WORMS, WITH OBSERVATIONS ON THEIR HABITS. BY CHARLES DARWIN, LL.D., F.R.S. WITH ILLUSTRATIONS SIXTH THOUSAND (CORRECTED) LONDON: JOHN MURRAY, ALBEMARLE STREET. 1882. The right of Translation is reserved. [page ii
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
CONTENTS. fine texture largely due to the action of worms—The disintegration of rocks by the humus-acids—Similar acids apparently generated within the bodies of worms—The action of these acids facilitated by the continued movement of the particles of earth —A thick bed of mould checks the disintegration of the underlying soil and rocks—Particles of stone worn or triturated in the gizzards of worms—Swallowed stones serve as millstones—The levigated state of the castings—Fragments of brick in
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
INTRODUCTION. already alluded to, which appeared in 1877. Before entering on details with respect to the castings, it will be advisable to give some account of the habits of worms from my own observations and from those of other naturalists. [page] [8
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
HABITS OF WORMS. CHAP. I. 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
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
HABITS OF WORMS. CHAP. I. 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 worm's 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
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
HABITS OF WORMS. CHAP. I. 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
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
action; for worms kept in pots covered by glass-plates, over which sheets of black paper were spread, and placed before a north-east window, remained during the day-time in their burrows and came out every night; and they continued thus to act for a. week. No doubt a little light may have entered between the sheets of glass and the blackened paper; but we know from the trials with coloured glass, that worms are indifferent to a small amount of light. Worms appear to be less sensitive to moderate
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
HABITS OF WORMS. CHAP. I. 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 with- drew 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
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
, and in paraffin, were held with pincers and were waved about within two or three inches of several worms, but they took no notice. On one or two occasions, however, when acetic acid had been placed on the pellets, the worms appeared a little uneasy, and this was probably due to the irritation of their skins. The perception of such unnatural odours would be of no service to worms; and as such timid creatures would almost certainly exhibit some signs of any new impression, we may conclude that they
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
CHAP. I. THEIR SENSES. both of which are devoured with much relish by worms. Small square pieces of fresh and half-decayed cabbage-leaves and of onion bulbs were on nine occasions buried· in my pots, beneath about 1/4 of an inch of common garden soil; and they were always discovered by the worms. One bit of cabbage was dis- covered and removed in the course of two hours; three were removed by the next morning, that is, after a single night; two others after two nights; and the seventh bit
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
various objects; and very young worms act in this manner. But some degree of intelligence appears, as we shall see in the next chapter, to be exhibited in this work, ─a result which has surprised me more than anything else in regard to worms. Food and Digestion. ─Worms are omnivorous. They swallow an enormous quantity of earth, out of which they extract any digestible matter, which it may contain; but to this subject I must recur. They also consume a large number of half-decayed leaves of all kinds
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
HABITS OF WORMS. CHAP. I. on a wall were so tough that they could not be gnawed by worms, but after four days they were affected in a peculiar manner by the secretion poured out of their mouths. The upper surfaces of the leaves, over which the worms had crawled, as was shown by the dirt left on them, were marked in sinuous lines, by either a continuous or broken chain of whitish and often star-shaped dots, about 2 mm. in diameter. The appearance thus presented was curiously like that of a leaf
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
HABITS OF WORMS. CHAP. I. the protoplasmic contents of the cells, we may infer that it resembles in nature not saliva,* but pancreatic secretion; and we know from Fredericq 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 in- dispensable for their disintegration by the unarmed mouths of worms that they should first be moistened and softened; and fresh leaves, however soft and tender they may
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
CHAP. I. CALCIFEROUS GLANDS. have been known to contain as much as 72 per cent. of lime. Worms therefore would be liable to become charged with this earth, unless there were some special means for its excretion; and the calciferous glands are well adapted for this purpose. The worms which live in mould close over the chalk, often have their intestines filled with this substance, and their castings are almost white. Here it is evident that the supply of calcareous matter must be superabundant
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
HABITS 0F WORMS. CHAP. I. decay generate an abundance of various kinds of acids, which have been grouped together und er 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
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
HABITS OF WORMS. CHAP. I. to such castings not having been recently ejected; for some which were at first acid, were on the following morning, after being dried and again moistened, no longer acid; and this probably resulted from the humus acids being, as is known to be the case, easily decomposed. Five fresh castings from worms which lived in mould close over the chalk, were of a whitish colour and abounded with calcareous matter; and these were not in the least acid. This shows how
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
CHAP. II. THEIR MANNER OF PREHENSION. seen on one occasion, when a large worm lying beneath a flaccid cabbage leaf tried to drag it away; for the surface of the leaf directly over the end of the worm's body became deeply pitted. On another occasion a worm suddenly lost its hold on a flat leaf; and the anterior end of the body was momentarily seen to be cup-formed. Worms can attach themselves to an object beneath water in the same manner; and I saw one thus dragging away a submerged slice of an
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
HABITS OF WORMS. CHAP. II. 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
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
HABITS OF WORMS. CHAP. II. 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
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
. 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 the worms on
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
burrows, no less than 16 were drawn in by the tips of the needles. These worms, however, worked in a careless or slovenly manner; for the leaves were often drawn in to only a small depth; sometimes they were merely heaped over the mouths of the burrows, and sometimes none were drawn in. I believe that this carelessness may be accounted for either by the warmth of the air, or by its dampness, as the pots were covered by glass plates; the worms consequently did not care about plugging up their
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
conclude that worms draw in some petioles of the ash by the base to serve as food, and others by the tip to plug up the mouths of their burrows in the most efficient manner. The petioles of Robinia pseudo-acacia vary from 4 or 5 to nearly 12 inches in length; they are thick close to the base before the softer parts have rotted off, and taper much towards the upper end. They are so flexible that I have seen some few doubled up and thus drawn into the burrows of worms. Unfortunately these petioles
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
the middle inch. In order to 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
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
CHAP. II. THEIR INTELLIGENCE. choice does not appear to be determined by the divergence of the two needles, and the consequent advantage or necessity of drawing them into their burrows by the base. With respect to the triangles of paper, those which had been drawn in by the apex rarely had their bases creased or dirty; and this shows that the worms had not often first tried to drag them in by this end. If worms are able to judge, either before drawing or after having drawn an object close to
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
HABITS OF WORMS. CHAP. II. 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 sup-position 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
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
four worms disappeared in 15 minutes between the sides of the pot and the earth, which had been moderately pressed down. On a third occasion three large worms and a small one were placed on loose mould well mixed with fine sand and firmly pressed down, and they all disappeared, except the tail of one, in 35 minutes. On a fourth occasion six large worms were placed on argillaceous mud mixed with sand firmly pressed down, and they disappeared, except the extreme tips of the tails of two of them, in
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
HABITS OF WORMS. CHAP. II. 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 worm's 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 Claparède, evidence in its favour must be given in some detail
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
HABITS OF WORMS. CHAP. II. 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
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
CHAP. II. EARTH SWALLOWED AS FOOD. seen; but not a single leaf was drawn into these burrows. These castings from their blackness and from the nature of the subsoil could not have been brought up from a greater depth than 6 or 8 inches. On what could these worms have subsisted during this whole time, if not on matter contained in the black earth? On the other hand, whenever a large number of leaves are drawn into the burrows, the worms seem to subsist chiefly on them, for few earth-castings are
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
leaf thus drawn in. Nor could any trace be discovered of the worms having crawled down the exterior surfaces of the towers in search of leaves; and had they done so, tracks would almost certainly have been left on the upper part whilst it remained soft. It does not, however, follow that these worms do not draw leaves into their burrows during some other season of the year, at which time they would not build up their towers. From the several foregoing cases, it can hardly be doubted that worms
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
HABITS OF WORMS. CHAP. II. unusual thickness. In this case the worms, judging from the castings, had pushed the cinders away on all sides and had not swallowed any of them. In another place, burrows similarly lined, passed through a layer of coarse coal-cinders, 3 1/2 inches in thickness. We thus see that the burrows are not mere excavations, but may rather be compared with tunnels lined with cement. The mouths of the burrow are in addition often lined with leaves; and this is an instinct
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F1362    Book:     Darwin, C. R. 1882. The formation of vegetable mould, through the action of worms, with observations on their habits. 6th thousand (corrected). London: John Murray.   Text   Image   PDF
effectually done, the sharp points would have prevented the retreat of the worms into their burrows; and these structures would have resembled traps armed with converging points of wire, rendering the ingress of an animal easy and its egress difficult or im-possible. The skill shown by these worms is noteworthy and is the more remarkable, as the Scotch pine is not a native of this district. After having examined these burrows made by worms in confinement, I looked at those in a flower-bed near, some
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