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bably provide new soils for hills and slopes where the rain washes the earth way; and they affect slopes, probably, to avoid being flooded. Gardeners and farmers express their detestation of worms;* the former, because they render their walks unsightly, and make them much work: and the latter, because, as they think, worms eat their green corn. But these men would find, that the earth without worms would soon become cold, hard-bound, and void of fermentation ; and, consequently, sterile: and, besides, in favour of worms, it should be hinted, that green corn, plants and flowers are not so much injured by them as by many species of coleoptera * (scarabs), and tipulæ (long-legs), in their larva or grub-state; and by unnoticed myriads of small shell-less snails, called slugs, which silently and imperceptibly make amazing havoc in the field and garden."
These hints we think proper to throw out, in order to set the inquisitive and discerning to work.
A good monography of worms would afford much enter
* We are indebted to Charles Darwin, Esq., for a remarkable and interesting memoir on the utility of the earth-worn, read before the Geological Society. The worm-casts, which so much annoy the gardener by deforming his smooth-shaven lawns, are of no small importance to the agriculturist; and this despised creature is not only of great service in loosening the earth, and rendering it permeable by air and water, but is also a most active and powerful agent in adding to the depth of the soil, and in covering comparatively barren tracts with a superficial layer of wholesome mould. The author's attention was directed by Mr. Wedgwood, of Maer Hall, Staffordshire, to several fields, some of which had a few years before been covered with lime, and others with burnt marl and cinders, which substances in every case are now buried to the depth of some inches below the turf, just as if, as the farmers believe, the particles had worked themselves down.
After showing the impossibility of this supposed operation, the author affirms that the whole is due to the digestive process by which the common earth-worm is supported; since, on carefully examining between the blades of grass in the fields above-mentioned, he found that there was scarcely a space of two inches square without a little heap of cylindrical castings of worms; it being well known that worms swallow the earthy matter, and that having separated the serviceable portion, they eject at the mouth of their burrows the remainder in little intestine-shaped heaps. Still more recently Mr. Darwin has noticed a more remarkable instance of this kind, in which, in the course of eighty years, the earth-worm had covered a field then manured with marl, with a bed of earth, averaging thirteen inches in thickness.
+ Farmer Young, of Norton-farm, says, that this spring (1777) about four acres of his wheat in one field was entirely destroyed by slugs, which swarmed on the blades of corn, and devoured it as fast as it sprang.
tainment, and information, at the same time; and would open a large and new field in natural history. Worms work most in the spring, but by no means lie torpid in the dead months; are out every mild night in the winter, as any person may be convinced that will take the pains to examine his grass plots with a candle; are hermaphrodites, and much addicted to venery, and consequently very prolific.
TO THE SAME.
SELBORNE, Nov. 22, 1777. DEAR SIR,—You cannot but remember that the 26th and 27th of last March were very hot days; so sultry, that every body complained, and were restless under those sensations to which they had not been reconciled by gradual approaches.
This sudden summer-like heat was attended by many summer coincidences; for, on those two days, the thermometer rose to sixty-six in the shade; many species of insects revived and came forth; some bees swarmed in this neighbourhood; the old tortoise, near Lewes, awakened, and came forth out of its dormitory; and, what is most to my present purpose, many
house-swallows appeared, and were very alert in many places, and particularly at Cobham, in Surrey.
But as that short warm period was succeeded as well as preceded by harsh, severe weather, with frequent frosts and ice, and cutting winds, the insects withdrew, the tortoise retired again into the ground, and the swallows were seen no more until the 10th of April, when the rigour of the spring abating, a softer season began to prevail.
Again, it appears by my journals for many years past, that house-martins retire, to a bird, about the beginning of October; so that a person not very ob ervant of such matters would conclude that they had taken their last farewell; but then it may be seen in my diaries, also, that considerable flocks have discovered themselves again in the first week of November, and often on the fourth day of that month, only
for one day; and that not as if they were in actual migration, but playing about at their leisure, and feeding calmly, as if no enterprise of moment at all agitated their spirits. And this was the case in the beginning of this very month; for, on the 4th of November, more than twenty housemartins, which, in appearance, had all departed about the 7th of October, were seen again, for that one morning only, sporting between my fields and the Hanger, and feasting on insects which swarmed in that sheltered district. The preceding day was wet and blustering, but the fourth was dark, and mild, and soft, the wind at south-west, and the thermometer at 587, a pitch not common at that season of the year. Moreover, it may not be amiss to add in this place, that whenever the thermometer is above 50, the bat comes flitting out in every autumnal and winter month.
From all these circumstances laid together, it is obvious that torpid insects, reptiles, and quadrupeds, are awakened from their profoundest slumbers by a little untimely warmth, and, therefore, that nothing so much promotes this deathlike stupor as a defect of heat. And, farther, it is reasonable to suppose, that two whole species, or at least many
indivi. duals of these two species of British hirundines, do never leave this island at all, but partake of the same benumbed state; for we cannot suppose that, after a month's absence, house-martins can return from southern regions to appear for one morning in November, or that house-swallows should leave the districts of Africa to enjoy, in March, the transient summer of a couple of days.
TO THE SAME.
SELBORNE, Jan. 1778. DEAR SIR,—There was in this little village several years ago, a miserable
who from his birth was afflicted with a leprosy, as far as we are aware, of a singular kind, since it affected only the palms of his hands and the soles of his feet.