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beneath that snow covering, either in seeds or underground buds, and they will come up again in their old haunts, delicate, beautiful, uninjured as ever! Who thus protects folded leaves and sleeping flowerets?
Even in winter, Nature with unwearied hand is ever preparing food for her plant-children, when they shall awaken from their slumbers. Frost and snow are of great service: the former breaks the hard masses, and renders the soil loose and porous; the latter spreads a warm covering over the landscape, thus protecting the numerous seeds of annuals and the underground stems of the perennials. Snow contains ammonia and other nutritive gases, and when it melts, the plants drink in its nourishing constituents. Thus when winter covers the earth with snow-storms, Nature is really benevolent, although apparently stern and unpitying.
EXPLANATION OF PLATE IX.
Fig. 1. One year's growth of beech-tree (Fagus sylvatica). a. Annular or ring-like scars, left on the bark by the winter leaves or
bud-scales. s. Cicatrix, or leaf-scar, left on the bark by the summer leaves. Fig. 2. Two shoots of the horse-chestnut tree (Æsculus hippoca tanum) placed
together for comparison. The left-hand shoot is the growth of a
single year, the right-hand shoot is the growth of ten years. a. Scars left by winter leaves.
s. Scars left by summer leaves.
s. Cicatrix, or leaf-scar, left by the summer leaves.
show1. The lamina or blade of the embryo summer leaf inverted on its
petiole, or its position whilst inclosed or packed away within the stipular leaves.
THE VINEGAR EEL
BY JABEZ HOGG, F.L.S., ETC.
S much doubt seems to prevail concerning the development
of the Anguillula, it appears to me a short history of these curious members of the animal creation will not be out of place in the pages of this Journal.
It was at one time believed that vinegar eels were produced “ in vinegar only (as stated in foot-note, at page 501, POPULAR SCIENCE REVIEW, July), without the addition of any kind of vegetable matter;" but modern means of research have greatly contributed to our knowledge of these as well as many other minute creatures. The microscope, assisted by chemistry, has exploded the old idea and demonstrated to our senses that scarcely a liquid or a solid is free from the attacks of one or other of the many varieties of fungi, the sporules of which, ever floating about in the air, are everywhere present, and ready, in some marvellous way, to initiate the work of either reconstruction or destruction, as the case may be.
A vast number of these fungoid growths are developed in fluids during the various processes of fermentation ; if, indeed, it may not be said of them, that they are the principal active agent in these apparently spontaneous reactions; all having a hidden period of incubation in these fluids, during which unseen stage they are causing the chemical changes in them, until finally a cryptogamic plant appears, multiplied a thousandfold, with each of its millions of sporules endowed with the original capacity of producing the same changes in the next fluid into which it may chance to enter.
We observe, also, another peculiarity in these low forms of vegetable life,—the remarkable facility they possess of assuming other forms and characters, which would appear to depend upon the nature and constitution of the fluid, soil, and habitat in which they were found. This fact led me to the probable conclusion, in my late paper on the Truffle, when noticing the ciliated motion before Anguillulæ made their appearance in the
I am now anxious that it should be known, that, upon making further examinations, I have not been able to verify the presence of cilia upon the ova; so that I believe the action observed must have been due to the presence
of some other minute animal or vegetable life; as vibriones, &c.
If we now turn our attention particularly to the development of the Anguillulæ, we shall find they constitute a very widely distributed family, belonging to a still larger order of the animal creation,—the Nematoidea, which abound almost everywhere. The whole genus were formerly classed with Infusoria, and arranged under variously distinctive names, mostly determined either by the substance or situation in which they were first discovered. The earliest contribution to the natural history of Anguillulæ appears in the writings of Turbervil Needham, under the heading of “Microscopical Observations on the Worms discovered in Smutty Corn,” published in the year 1744, in a paper contributed to the Philosophical Transactions of the same period. He very correctly describes these worms, as he called them, and their economy, illustrating one memoir by tolerably correct figures. Yet, in a subsequent paper, he most unaccountably retracts everything he before had written respecting them, and declares “the white fibrous creatures in the interior of the corn to be true zoophytes.”
Maurice Roffredi, in his memoir “ Sur l'Origine des petits Vers ou Anguilles du Bled rachitiques,” which appeared in vol. v. of the Journal de Physique, 1775, fully describes the Anguillulæ. He seems to have attentively observed their whole economy and many other peculiarities in the various stages of existence, although he fell into some errors with regard to their early development in the corn. He also was the first to communicate, or enoculated,” as he terms it, the disease to rye and barley, by transferring young eels to both these grains, and in which they became as quickly developed as in wheat grains.
F. Fontana also published some remarks on these minute creatures in 1776 ; but he fell into many errors concerning them : first, he maintained that the infected grains in which the eels are foundAre extraneous tumours, or gall-nuts the mere produce of the worms; and, secondly, that the suspension of life, or muscular action, is neither a state of torpor nor suspension, but real death or extinction of life ; and that they are brought to life again as often as they are moistened with water.
But the clearest and most trustworthy account of the Anguillulæ appears in the Philosophical Transactions of 1822, by a Fellow of the Royal Society, Francis Bauer, in a memoir “ On the Muscular Motion of the Vibrio Tritici ;” and the point which struck this observer most,-indeed first led him to study them,
was their remarkable power of life. He commences by telling
Having left some of them on a glass for some four or five days, they were dried up and apparently dead; but upon again moistening them with water, much to his surprise, in a very short time they began to show signs of life, and in the course of an hour were as lively as before. This experiment he made again and again, with the same results; but found that those which had been kept the shortest time under water recovered their motions soonest; so that, after a second or third suspension, at intervals of a week or ten days, they could not be revived.
If, however (he says), the second experiment be not made too soon after the first, the chances of recovering are greater. The longest interval, after a second suspension of life, I was able to recover them, was eight months. If, when first revived, they are kept in water, excluded from the air, and evaporation prevented, they remain alive and propagate for many months.
Their eggs have an extremely delicate transparent shell or structureless membrane, throngh which the young can be attentively observed. With some care it may be seen moving within its envelope, and, by a spinal motion, at last breaks through and escapes. The egg measures about the oth of an inch in length; and soon after the young animal quits the shell, it shrivels up and disappears.
Each single grain of corn contains many eels. Bauer found
Seven full-grown and a hundred young eels, all alive, beside a great many eggs ; and, upon being placed in water, they were seen twisting and wriggling about, like so many serpents.
He experimented upon grains, after keeping them for five years and eight months, and always with the success narrated ; but he found the corn required to remain under water a much longer time before the eels were resuscitated. When they die, they remain in water, unaltered in form and character, for many days or weeks.
He supposes the glutinous substance which surrounds the eels, when he cut open the corn, Must be secreted by them; since, in the infected grains, the cellular tissue has entirely disappeared. From this fact, we may consider that the glutinous substance preserves the young animals from further change; and what is recorded of the snail, which can, by its own mucus, hermetically seal itself for thirty years in its shell against a wall, is similar to this.
I have resuscitated them after the infected corn has been allowed to lie excluded from light and air for upwards of eight years. Indeed the whole of the species are most remarkable for their great tenacity of life, resembling in this particular the Tardigrada and Rotatoria.
The various species of the Anguillula most familiar to microscopists are-1st, Ang. Tritici of blighted corn,-wheat, &c.; 2nd, Ang. Aceti, of vinegar, or in any substances undergoing acetous fermentation ; 3rd, Ang. Glutini, of sour paste, so precisely similar to A. Aceti, although authors still persist in describing it as distinct, is nevertheless exactly the same in every particular ; and 4th, Ang. fluviatilis, found in waste waters among the decaying vegetable matters, as well as in wet moss, boggy districts, and moist earth.
It will be observed that wherever the Anguillulæ have been found, they are invariably developed in, and probably live upon, the decaying vegetable substances. The ova of these creatures are so minute, that when the earth or vegetable matter is dried up and converted into fine dust or powder, the wind takes it
and it is driven about hither and thither over the face of the earth. The microscope has failed, as yet, to demonstrate the presence of ova mixed up with earthy or vegetable matter, before it becomes infused into the liquid material, which swells out the mass, and calls it into new life and vigour. Yet that the ova must be present, no reasonable mind can doubt, as we soon discover some chemical change going on, and suddenly the whole is converted into colonies of living eels; and such is the tenacity with which they cling to life, that no amount of exposure to either heat or cold, or other climatic influence, is able to entirely extinguish it.
Thus, it appears, from the observation of trustworthy observers, that Ang. fluviatiles have been exposed to the scorching heat of a summer's sun, until perfectly converted into the finest powder or dust; nevertheless the first gentle shower of rain descending upon some of this at once begins to swell it up, softens it, and, finally, creatures sporting in the sunshine appear in all stages of growth, taking food, and exercising all the various functions of the higher-organized animals. What is still more extraordinary is, that some of them delight in