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to the viscid yellowish substance and transparent cations, to the most complex plants, which we are fluid sap.”—The Plant, p. 44.
compelled to look upon as the highest states.
“ The forms immediately following the aboveOther leaves and other pulpy fruits will mentioned simplest plants, also consist of a simple be found to contain cells in equal abundance often branched-thus exhibiting a higher develop
cell; but this is elongated into a filament, and with those mentioned by Schleiden. In the ment of form. Next, the cells arrange themselves pulp of a fully ripe orange they are of large into lines in manifold ways; a variety of forms of size and filled with the colored juice; and vegetation soon grows up, which, in water, apthe pith of all plants is entirely composed of pear as the silk-weeds or confervas-generally of a them, without any intermixture of the other green color; or on decaying organic bodies, as elementary organs. In this cellular form, forms, with the most brilliant play of color. Then
moulds, in very various and often most elegant and in that of a transparent extended mem
the cells unite to compose flat structures, known brane, formed by the cohesion of a number to botanists by the name of ulvas; and, frequentof cells, and called cellular tissue, this is the ly growing in the sea, almost like young lettuce only elementary organ universally found in leaves, sometimes green, sometimes red, often afplants; the other forms, hereafter to be ford a meagre meal to the poor inhabitants of the spoken of, being often either partially or al-coast. Next they crowd together into solid masses, together wanting: as is the case with the formning clumps and balls of the greatest possible whole of the plants comprised in the class, variety of shapes.”—The Plant, p. 93. termed by Professor Lindley, Thallogens,
It is among the simple plants above spoken which are mere masses of cells, offering no distinction of root, stem, or leaves ; and, hav- with those curious and most anomalous or
of as silk-weeds, or confervas, that we meet ing no flowers, are not reproduced by seeds, ganisms, of whose animal or vegetable nature properly so called, but by minute anomalous it is impossible to predicate with certainty, bodies termed spores. To this class belong without calling in the aid of chemistry; for the confervas, sea-weeds, lichens, and fungi; here external appearances afford us no assistand there are so many curious circumstances connected with these simply organized plants,
ance in our investigations. that we may well be excused if we linger “The Zoologist,” says Professor Lindley, “ deawhile among them, especially as the lowest clares that the power of spontaneous motion, and members of the class are now generally con- the feeding by a stomach, are qualities confined sidered to occupy a point at which it seems
to the animal kingdom. But numerous plants impossible physiologically to distinguish be move with all the appearance of spontaneity; the tween the animal and vegetable kingdoms, so
spores of those Confervæ which are sometimes
called zoosporous, swim in water with great as to be able to say with certainty where the activity; the filaments of Zygnemata combine one ends and the other begins.
with the energy of animal life ; and as for a
stomach, it is impossible to say that the whole “Regarding the vegetable kingdom as a whloe, interior of a living independent cell is not a as an individual,” says Schleiden,
“the various stomach." stages of life and development of which lie as Without, however, attempting in this place close beside each other, as they follow after one another in a single plant, we are enabled to regard select a few curious examples of circum
to settle so vexed a question, we will simply the simplest form as also the commencement of the Vegetable World; and then we find that this, stances attending the reproduction of these like the individual plant, is produced and devel- | lowly beings, well calculated at once to oped from a simple cell. When, on old damp puzzle the naturalist, and to demonstrate the walls and palings, or in glasses in which we have truth of the axiom-De minimis et de maxlet soft water stand for several days in summer, imis æquè curat Natura.” we find a delicate bright green and almost velvety Those beautiful living ornaments of the coat, we meet with the first beginning of vegetation. Under the microscope, we detect in these drawing-room-gold-fish — frequently begreen masses a number of small spherical cells
come diseased in a very peculiar manner. hilled with sap, colorless granules, and chlorophyll
. They are infested by a white, mouldy-like In other places occur similar cells, but yellowish, substance, which eventually spreads over brown, or red; and almost all, at least at present
, and destroys them. This substance, which may be regarded as perfect plants, which have is now ascertained to be a confervoid plant, received various names from botanists. The
and has received the name of Achyla prolimost suitable name for them is Protococcus, or primary resicle. From this simple cell
, vegetating fera, has been carefully examined by Unger; as an independent plant, the development of the and Dr. Lindley thus describes some curious vegetable world takes its departure, and ascends particulars connected with it.
He says of by continually greater combinations and compli- | the Achyla, that,
“When arrived at its full growth, it consists of Conferva area, a fresh-water Alga not untransparent threads of extreme fineness, packed common in our own country; and Unger has together as closely as the pile of velvet ; they described it as observed by himself in those greatly resemble, in general appearance, certain kinds of mouldiness. These threads are termi
of Vaucheria clavata, also a British plant. nated by an extremity about the 1,200th of an Agardh, in a memoir on the germination of inch in diameter, consisting of a long single cell, the spores of several Algæ, in the “ Annales within which is collected some green mucilage des Sciences Naturelles,” for October, 1836, intermixed with granules. Dr. Unger assures describes the mode of escape of the reprous that, at this time, no starch is present; but ductive granules of the Conferva above the whole of the green matter is of the nature of named, as well as their subsequent developgom, as is proved by the action of iodine upon it. ment into articulated or jointed filaments, The contents of the cell are seen to be in constant motion. While this is going on, the end of resembling the parent plant. After escapthe cell continues to grow, and, at the same time, ing from the cells that make up the length the contents collect at the extremity, and distend of the filament, which they do through the it into a small head, in form resembling a club; sides of those cells, the green granular immediately after which a chamber is formed, and sporules are said to “continue their motion then the first stage of fructification is accomp- for one or two hours, and retiring always lished. The next change is observed to take place in the granular matter of the club-head, towards the darker edge of the vessel, somewhich itself enlarges, while the contents gain times prolong, their wandering courses, opaqueness, and by degrees arrange themselves sometimes remain in the same place, causing in five or six-sided meshes, which are in reality their beak to vibrate in rapid eircles. Finally forming at the expense of the mucilage above they collect in dense masses, containing inmentioned, which has disa ppeared. It is not the numerble grains, and attach themselves to least surprising part of this history, that all the changes above mentioned take place in the course
some extraneous body at the bottom or on of an hour or an hour and a half; so that a pa- the surface of the water, where they hasten tient observer may actually witness the creation
to develope filaments like those of the mother of this singular plant. At this time, all the vital plant. The spherical sporules elongate at energy seems directed towards changing the first into egg-shaped bags, attached to the angular bodies in the inside of the club-head into strange body by the narrowest end. Their propagating germs or spores. Meanwhile, the development only consists in a continued exclub-head they in their turn alter their form and become pansion, without emitting any root. The oval
. Then it is that is witnessed the surprising green internal matter divides in the middle phenomena of spontaneous motion in the spores, by a partition, which appears at first sight which, notwithstanding the narrow space in
as a hyaline mucilage, but which gradually which they are born, act with such vigor that at changes into a complete diaphragm. It is last they force a way through the end of the thus, by successive divisions of the joint first club-head. At first one spore gets into the water, formed, that the young plant increases.” Dr. then head is emptied. All this takes place with such Agardh then observes, that “in this man
ner the formation and dissemination of the rapidity, that a minute or two suffice for the complete evacuation of the club-head or spore- seeds continues during the whole summer ; chamber. The spores, when they find their way and thus a single filament suffices for the into the water, are generally egg-shaped, and formation of an infinite number of sporules;" swim with their small end foremost; but they are and, “if one remembers that each joint often deformed, in consequence of the narrowness contains perhaps many hundreds of spores, of the hole through which they have had to pass. it is not astonishing that the water becomes It even happens that they stick fast in the hole, and perish there. They are extremely small, perfectly colored with them; so that we their breadth not exceeding
the 1,896th part of an might readily take for a Protococcus, or other inch. Their small end is the most transparent, simple Alga, what are only the spores of a and it is curious to see how constantly this is Conferva.' The author thus sensibly conpushed forwards in the rapid evolutions made in cludes his interesting account of these the water by these living particles. This sort of anomalous organisms : "I suspect that from quasi animal life does not last long--a few se such a mistake have arisen the theories of conds, some minutes, or at the most, half an hour. They often die: Unger assures us that he metamorphosis proposed by many modern has seen them in the agonies of death, and strug. algologists.” gling convulsively (!), with all the appearance of The presence of cilia upon these minute animal life.”—Vegetable Kingdom, p. 18. sporules has not been satisfactorily made out,
even with a high microscopic power; but A similar kind of motion has been observed that their motions are due to the vibratile by the accurate Agardh, in the spores of action of cilia is highly probable, from a hyaline border being observed around them, with a more complicated organization besimilar to that surrounding the ciliated Infu- come developed from the simple primary cell soria, when viewed under a microscope of form. insufficient power. Our first acquaintance In speaking of the formation of the articuwith what we have since suspected must have lated filaments of Conferva ærea from the been the sporules of this or an allied species floating spores of that plant, it was stated of Conferva, occured many years ago, be that after the sporules have anchored themfore we had paid any attention to the Algæ. selves to some extraneous body, they at first At the bottom of a leaden cistern, containing elongate, and then divide by an internal rain-water quite freely exposed to the air, partition into two portions, each of these and having numbers of the long, loose, green again dividing, and so on; the young plant Confervæ floating from its sides, had gradu- gradually lengthening by these successive ally accumulated a quantity of vegetable divisions. This, however, is not the only refuse-cabbage-stalks, leaves, and so forth. mode in which the primary vesicle gives On a bright summer's day we observed birth to others; which again, by successive that the water, which had previously been multiplications and reproductions, at length perfectly limpid and colorless, had become form a plant possessed of a more perfect, or turbid, and assumed a dull green color. On rather a more complicated organization. It examining some of this water under a high must, however, be borne in mind, that we power of the microscope, we found that the are at present treating of those plants in color and turbid appearance was caused by which no other elementary tissue than the myriads of excessively minute Infusoria, as cellular is present. we then thought them, swimming about in all directions with the greatest rapidity, and “ If,” says Schleiden, “the nutrient matter exhibiting the hyaline border mentioned by within the cell increases in quantity beyond a Agardh. In a few days they entirely dis- certain measure, new cells are formed from it appeared, and we never afterwards had an within the first, called secondary, or daughteropportunity of observing them in anything the mother-cell then gradually dissolves and dis
cells; they propagate, and in the usual course like similar abundance. But as a curious sequel to the disappearance of these little appears, while the two, four, eight
, or more
young cells produced by it, occupy its place. The green bodies, may be mentioned the subse whole process which we call growth in plants, quent development, in nearly equal profu- consists in its essential elements of a continuous sion, of the rather rare wheel-animalculæ, propagation of cells of this kind, whence the which gave the water a milky color; and number of cells becomes multiplied beyond calcuthese, in their turn, became extinct.
lation, nay, almost beyond credibility. From an The active spores of the Confervas above approximate calculation, for example, in a rapidly
growing fungus, Bovista gigantea, 20,000 new spoken of, as well as the individual members cells are formed every minute.”—The Plant, of the colored matters upon walls and rocks, named Protococcus, to which the so-called red snow of the northern regions has been In his excellent work “ On the Growth of referred, are sufficient proofs of the ability of Plants in closely-glazed Cases,” Mr. Ward the simple cell to subsist as an “independent mentions his having watched the rapid organism, living for itself alone,” and imbib- growth of another fungus, Phallus foetidus, ing “fluid nutriment from the surrounding which, “in the course of twenty-five minutes, parts; out of which, by chemical processes shot up three inches, and attained its full which are constantly in action in the interior | elevation of four inches in one hour and a of the cell, it forms new substances which half.” Mr. Ward, however, attributes this are partly applied to the nutrition and rapid development, not to the multiplication growth of its walls, partly laid up in store of the number of cells, but to “an elongafor future requirements, partly again ex- tion of the erectile tissue of the plant." But pelled as useless, and to make room for the surely this almost amounts to the same thing; entrance of new matters. In this constant for to what is the elongation of tissue owing, play of absorption and excretion, of chemical except to an increase in the number of cells formation, transformation, and decomposition composing it? of substances, especially consists the life of The fungi to which the two last-named the cell, and—since the plant is nothing but plants belong, compose a vast group, of the a sum of many cells united into a definite vegetable nature of which there is no quesshape-also the life of the whole plant.” tion, notwithstanding that in addition to the We will now consider in what manner plants | usual chemical constituents of vegetable
tissues-oxygen, hydrogen, and carbon—a | among plants, as well as humans, prefer fourth element is now found to exist in great | darkness rather than light, for making inabundance, which was formerly looked upon roads upon their neighbors' property. This, as affording the only mark of distinction be indeed,' is particularly the case with the tween plants and animals. This element is plants we are now speaking of. nitrogen. But we need not here pause to Like insects, fungi do not content themdiscuss the chemical constituents of the selves with preying upon dead organized fungi; our business at present lies rather matter; some of them also attack living with their external forms.
substances, both animal and vegetable. Few persons except those who have They have been found growing in the airstudied the subject would suspect that either cells of birds, and even upon the lining the delicious mushroom, the poisonous toad- membrane of the human lungs. The comstool, or the puff-balls of our pastures, bear mon house-fly may frequently be seen in any relationship with the mouldiness and autumn attached by its proboscis to the mildew which so speedily overrun books, glass of windows, and covered with a mouldpapers, boots and shoes, and other articles like fungus.
sometimes of clothing and domestic economy, when destroyed in vast numbers by an internal lying neglected for a time in damp situations, fungus termed muscardine. A species of yet such is the case. In these attacks, the wasp, inhabiting the West Indies, may minute fungi are but lending their aid to often be seen flying about with fungoid insects in performing their great office of plants as long as its own body growing
scavengers of nature,” by hastening the upon it; and, to mention no further examdecomposition and subsequent removal of ples of parasitic fungi, the caterpillar of a dead and decaying animal and vegetable New Zealand moth, when it retires into the substances, which are thus rendered capable earth to undergo its change into a chrysalis, of entering into new combinations, and of is attacked by a species named Sphæria running through a new career. “ It is this Robertsii, which destroys it. A very curious property,” says the Rev. M. J. Berkeley, circumstance connected with this fungus“which renders one or two species, known bearing caterpillar is, that, in all the exunder the common name of dry-rot, such a amples we have ever seen, the plant invadreadful plague in ships and buildings.” riably grows from immediately behind the This disease, once established, spreads with head of the victim, and from no other part of wonderful rapidity. Professor Burnet re- its body. cords the following instance of the speed The instantaneous appearance of the with which a building may be destroyed by simpler descriptions of fungi—such as milthis insidious
dew, mouldiness, and dry-rot — together
with the curious and unexpected localities “I knew a house into which the rot gained wherein they frequently occur ; as well as admittance, and which, during the four years we rented it, had the parlors twice wainscoated, and such as mushrooms, toad-stools, and the
the rapidity with which the larger species – a new flight of stairs, the dry-rot having rendered it unsafe to go from the ground floor to the bed-like-spring up, and attain their full develrooms. Every precaution was taken to remove opment in favorable localities; and, more the decaying timbers when the new work was than all, the apparent impossibility of the done ; yet the dry-rot so rapidly gained strength, introduction of anything like seeds into many that the house was ultimately pulled down, places where fungi are sometimes found Some of my books which suffered least, and mouldiness, for example, in the very centre which I still retain, bear mournful impressions of a large apple—all tend to give an air of affected, that the leaves resembled tinder, and plausibility to an idea by no means as yet when the volumes were opened, fell out in dust exploded, that these plants are the products or fragments."
of spontaneous or equivocal generation—in
this particular, also, bearing an analogy to The rapidity with which fruit-preserves insects, many of which are likewise supposed become covered with mould, is another in- to owe their being to the same unphilostance of the avidity of the fungi in seizing sophical cause. But a vegetable seed is no upon any spot that may suit their fancy ; less required for the production of the most and if it be true that those jars of preserves minute speck of mouldiness the microscope which are not left open for a night before can reveal to our view, than is the animal they are tied down, are less liable to become egg for the primary stage of the most highly mouldy, the fact only shows that ill-doers organized vertebrate animal; and as in the animal kingdom, so in the vegetable, in pro- reaching a proper nidus, and attaining the portion as we descend in the scale of organi- conditions requisite for germination. And as zation, the due perpetuation of the species the spores of all species are produced in corseems to be the more earnestly cared for. responding numbers, according to their size The fungi are, individually, exceedingly and kind, it requires no great stretch of imagfugitive in their nature, and the duration of ination to conceive that they float about, like individual life among them is very brief; all motes in the sunbeam, until
, alighting on a their energies, as has been well observed, locality furnished with all proper conditions, seem to be directed to the production of new they germinate, and each produces an indiviindividuals, destined, in like manner, to con
dual like the parent. tinue the race.
The mycelium, or creeping flocculent stem We have seen, that in the silk-weeds or of fungi, is well known to all who cultivate confervas already spoken of, the reproduc- the mushroom ; it is the substance called tive bodies or sporules are produced within spawn. The mushroom itself is properly the body of the plant, which consists simply the fruit, or seed-producing portion of the of a filament composed of a number of cells plant, the germs or sporules of which are placed end to end. In the fungi we find a borne in the gills; and to the peculiar mode considerable advance upon this. The fil- of growth of one species of the mushroom amentous portion is present, but we have, in family, is due those“ green sour ringlets" addition, a body expressly destined to the well known as fairy rings. A floating spooffice of producing the sporules. Thus, the rule of this plant falls in a locality suited to common blue mould upon cheese and other its growth. On germinating, it sends forth substances, if examined under a microscope, in all directions, from itself as a centre, a will be seen to consist of a flocculent base of number of the flocculent branched threads, entangled branching filaments, from which like horizontal rays : these anastomose, and arise a number of simple, erect threads, each form among themselves a circular net-work bearing on its summit a little round body of fibres. At the circumference of this cirfilled with a very light buoyant dust. And cular net-work are produced the mushrooms this, with certain modifications, will pourtray or fruit, in the form of a circle; which is very the mode of growth and of fructification of small the first year, but gradually extends at all the fungal tribe. Being what are botani- the circumference as the central part dies, cally called flowerless plants, they have the fruit being thus, year by year, carried nothing to correspond with the flowers of further away from the centre, and the circle the more highly organized members of the enlarging. From increased fertility in the vegetable kingdom. They are simply con- soil, or some other cause, the grass at the fined to the possession of organs of growth circumference of the circle is always of a and organs of reproduction; the former more vivid green than that beyond it or within typified by the flocculent creeping filaments ; it; probably, the decay of the more recentthe latter, which may also be called the ly-formed mycelium may impart a degree of fruit, by the little round balls filled with fertility to the soil superior to that where the dust, the dust itself being analogous to the decayed matter has already been elaborated seeds of flowering plants.
afresh by the grass or the Agaric. And The puff-ball, one species of which has thus are formed those emerald rings, by already been mentioned as forming 20,000 some authors attributed to the effects of new cells every minute, and which has been electricity, but which the poets have more known to grow from the size of a pin's head pleasingly ascribed to the fairies ; either as to that of a large gourd in one night, is the traces of their moonlight revels, or, as merely the fruit of the underground creeping our own Shakspeare sings, in a strain which stem, technically called mycelium or spawn. may well relieve this dry disquisition on the The immense number of sporules produced fungi, as a mark of honor peculiarly applicaby these puff-balls, when ripe, may be in- ble to the royal precincts of Windsor. ferred, when it is stated that they escape from the large globular head, on its being “ And nightly, meadow-fairies, look you sing, pressed, like a cloud of smoke. In a single
Like to the Garter's compass, in a ring : specimen of Reticularia maxima, a fungus
The expressure that it bears, green let it be,
More fertile-fresh than all the field to see; growing upon the trunks of felled trees,
And, Iloni soit qui mal y pense, write, Fries reckoned upwards of 10,000,000 of
In emerald tufts, flowers, purple, blue, and sporules, each probably capable of develop
white : ing into a new individual immediately upon Like sapphire, pearl, and rich embroidery,
VOL XVIII. NO. II.