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the superiority of things which are ex or pure carmine, the experiments were cellent.
G. T. L. successful.
When a minute portion of a very weak
solution of -indigo is added to a drop of ANIMALCULES.- No. II.
water, containing vorticellæ, an ani. We may now pass on to notice the mated scene ensues : eager for the food, digestive apparatus of these minute be- which they swallow with avidity, ings, as far as it is ascertained ; but they throw the cilia into rapid action, before entering into the subject, it must producing currents in the water, hurrybe premised that in many points great ing with them the particles of the inobscurity prevails, and that the observ- digo, in gyrations converging to the ations of Ehrenberg are not always mouth. In a short time, a number of corroborated by those of other micro- dark blue circular dots begin to show scopic investigators. The term poly- themselves on the transparent body of gastrica, by which the present group the animalcule, which are occasioned of animalcules is distinguished, bears by the particles of the indigo accumureference to the complexity of the di- lated in these situations ; they also make gestive apparatus, which is stated to manifest the intestinal tube, and their consist of a number of internal sacculi, progress can be gradually traced through or stomachs, in some, arising from the its extent. It was thus by a series of mouth itself by separate tubes, (see the experiments, that Ehrenberg was at
length enabled to determine the number of the sacs, or stomachs, and course of the intestinal tube. But it appears that all the sacs are not filled at the same time; many continue long without receiving any particles of colouring matter, and the whole course of the alimentary tube is not simultaneously tinted. The number of sacs thus distinguished, amounts to two hundred in some spe
cies ; in others they are less numerous. annexed figure,) in others, appended to It is on the characters and positions a kind of intestinal canal, which tra- of these sacs, and on the course of the verses the body, and terminates either presumed intestinal tube, that Ehren. at the extremity of the body opposite berg has founded the divisions of this to the mouth, as in Paramecium au- class ; but Professor Jones, while he relia, (page 50,) or which, winding up, acknowledges that the views of this terminates in a depression near the naturalist are sanctioned by general conmouth, as in Vorticella (page 51.) The sent, is not disposed to admit their acsacculi, though distinguishable in the curacy in all respects, and states that animals under ordinary circumstances, his own observations (made by means are rendered more conspicuous when of a compound achromatic microscope, the animals have swallowed water in and employing powers nine-tenths, onewhich colouring matter is suspended, half, one-fourth, and one-eighth of an in a state of very minute division, but inch focus) have led to very different not chemically dissolved. Trembley, in conclusions. The positions of the ori. his investigation of the structure of the fices for the reception and rejection of hydra, adopted this method, and Glei- aliment he found to be such as Ehcher attempted it, though unsuccess- renberg has indicated; but the most fully, in his investigations upon these patient investigation did not enable him animalcules. The fact is, that many to detect the arrangement of the tube, of our metallic or earthy colouring ma and the sacculi appended to it, as terials immediately poison these crea- figured and described by that author. tures, when of course the experiment He states that he has never been able fails. This Ehrenberg tried in vain, to perceive, when one of the carnivorous with the indigo and gumlac of com- animalcules has swallowed another that merce, these substances being always it has been conveyed, as contaminated with a slight admixture expected, into one of these, so called of white lead, which acts as an instan- stomachs, but that he has traced it into taneous poison ; but with pure indigo, “what seemed a cavity excavated in
was to be
the general parenchyma of the body.”, tinged with the juices of the prey on In the next place, he states that these which the animal feeds; which juices, sacculi have no appearance of being at- by some means unknown at present, tached to any tube by means of pedun- | they absorb, and thus charged, circucles, or necks ; and that in Paramecium late through the gelatinous substance aurelia (page 50,) so far from appearing of the body. We may here, by way to be connected with a central canal, of note, observe, that some observations as is represented by Ehrenberg, they respecting the hydra, or fresh water are in continual circulation, moving up polype, will be found in “Notes on the one side of the body and down the other, Month,” for June, pages 204—207 in and even changing their relative posi- the Visitor for 1840. tions, like the coloured granules visible With respect to the mouth of the in the gelatinous substance of the hydra. polygastric animalcules, it is generally And, thirdly, he affirms that in no in- found to be a simple dilatable and constance has he been able to detect a tractile orifice; but in some species it central tube at all, as depicted by Eh- appears under the form of a small prorenberg, much less the branches leading jecting beak, or rather tube, composed from it to the sacs; and he adds, that of numerous teeth of an elongated shape, the circumstances attending the prehen- and calculated both for the prehension sion of food, would, in themselves, lead of food, and for bruising it previously us to imagine a structure different from to its being swallowed. In these spethat described by Ehrenberg. He ad- cies, the mouth does not appear to be duces, by way of confirming his views, surrounded with cilia, which would be the changes of form which these ani- unnecessary,
but which, when the malcules undergo, when devouring prey mouth is a simple orifice, are required nearly equal to themselves in bulk, and for the direction of the food to it. therefore incapable of entering into one There is no part of the history of of these sacs ; the mouth dilates to these polygastric animalcules, more calengulph the victim, and when this is culated to excite astonishment than that swallowed, the whole body, as in the relative to their mode of reproduction, hydra, becomes greatly distended. As so different from that of other races of an example in point, Professor Jones beings; and what is surprising, is, that figures the flask animalcule (Enchelis the same individual, as it would appear, pupa) in its ordinary state, preparing often reproduces in four different ways. to attack its prey, in the act of en First, then, one mode of reprogulphing it, partially swallowed, and duction is by gemmules or buds, wholly so. (See the engraving.) For other sprouting from the outer surface of the
parent, as in the hydra. These little buds gradually assume their destined form, develope cilia, and become detached and independent, and in a short period afterwards attain to their full growth, giving origin to buds them. selves.
Secondly. Another mode, which is
seen in Volvox globator, is by mid
nute globular bodies, of a dark green colour, covered like the parent with
vibratile cilia, and which swim about information on this doubtful point, re
in the interior of the body of the parent, specting the structure of the digestive where they appear to have ample space. apparatus of the polygastrica, see his The transparency of this animalcule, valuable work, entitled, “ A general Out- which is of a globular figure and of a line of the Animal Kingdom.” When delicate green, permits the germs it two observers are thus at issue, when encloses to be readily seen,
When they their respective investigations conduce have attained a proper degree of deto results so different, we must wait for velopement, the outer skin of the parent farther experiments. It is however re- bursts, and they emerge from their markable, that in the hydra the gra- imprisonment, to undergo a like destiny: nules already referred to, which are Thirdly. The most usual mode, and certainly not stomachs, also become it is the most extraordinary, by which
new animalcules are produced, is by above sketch will illustrate the progress the division of the animalcule itself detailed, and also show the new animalinto two or more portions, each por- cule, after gaining its freedom, in three tion becoming a perfect being, and different forms. again dividing in turn. In animalcules There is still another mode of reproof an elongated form, the division gener- duction by division : it occurs in animalally takes place longitudinally, each side cules which appear, as the gonium, to conbecoming a distinct being, with all its sist of a number of globules, (sixteen in organs complete ; but in oval animal one species,) enclosed in a thin transpacules, the division is transverse, first rent envelope; the mass thus compounded beginning with a median constriction divides in this species into four equal which traverses till the separation is parts, each part containing one large effected. Some animalcules increase and three smaller globules: After their both by gemmules, and by division, separation from each other, these parts as the convallaria, but chiefly by the swim freely about in the water, and latter. The convallaria resembles a increase in the number of their conbell-shaped flower, supported upon a stituent globules, to undergo a fresh slender footstalk, by which it is attached division. In other species, the division to fixed objects. This slender footstalk is into still more numerous portions. is highly contractile, and winds round Fourthly. Some animalcules increase in a spiral manner, when the animal by division, by gemmules, and by eggs is alarmed, and thus withdraws it from
or spawn. danger. The division only takes place In the Kolpoda cucullus, Ehrenin the bell, which first increases in cir- berg detected, most satisfactorily, the cumference, and begins to divide at its latter mode, and he describes the eggs, margin, the fissure gradually extending when excluded, as appearing in the to its base; when the fissure is com form of a delicate mass resembling netplete, one half is found perfect, and is work. destined to continue on the footstalk, No mode of reproduction is more and may therefore be regarded as the wonderful than that of division, none parent of the other, which is now at so productive. It is wonderful, when tached by a slight connexion to the top of we consider that each divided part has the footstalk by the side of the perma- to assume all the organs of the perfect nent bell, which is found to have cilia not being, that these have therefore to beonly at its upper margin, but also around come developed, and to assume their its base. It now becomes detached and due form and situation. And as to proloses the marginal cilia, retaining the ductiveness, the Paramecium aurelia, basal ones, and thus it swims about: /well supplied with food, has been obbut it has not yet developed its footstalk; | served to divide once in twenty-four this it gradually puts forth, the adult hours, so that, as Professor Jones obstage is then acquired, and it becomes serves, “in a fortnight, allowing the fixed to some foreign body, like the product of each division to multiply at parent when it sprung. While, in its the same rate, 16,384 animalcules would free condition, this animalcule assumes be produced from the same stock," and various modifications of form, and in in four weeks the astonishing numthese states has been described as so ber of 268,435,456 new and distinct many distinct species ;, and it is by beings. recent observations only that its real Now let us pause, to reflect upon character has become known. The power of that God, who has created
chese creatures for our examination, and for our instruction ; perhaps, though we know not in what, for our benefit. Their minuteness confounds us; their numbers overwhelm us; their habits surprise us; their history teems with wonders. Difficulties meet us at every step; and we are forced at length to confess that the work of God contains mysteries, which baffle the penetration of philosophy.
Brush Turkey of Australia. Talegalla Lathami, Gould.
belongs. The second is also a galliNo portion of the globe contains ani naceous bird, and has been recently mals so singular in their structure, as made known to science by that enterAustralia ; in no other region does the prising naturalist, Mr. Gould. It is naturalist find beings so strangely orga- from his magnificent work on the birds nized, or so extraordinary in their habits. of Australia, which, from its expense, We need not offer proofs of this asser can only be in the hands of the few, tion; they will suggest themselves to that we derive our account. the mind of every one who is acquainted The brush turkey, or, as Mr. Gould with the ornithorhynchus, the echidna, terms it, the wattled talegalla, inhabits the kangaroo, and the wombat. The various districts of New South Wales, truth, however, of the proposition, as from Cape Howe on the south to Morefar as regards habits, is strikingly ex ton Bay on the north. In some places, emplified in the history of two birds where it was once common, it has now peculiar to Australia, and of which we become rare ; and we learn that the are about to give the details.
cedar cutters, and others who are in The two birds to which we here the constant habit of hunting through allude, are the brush turkey of the the brushes of Illawara and Maitland colonists, called wee-lah by the abori- have nearly extirpated it from these gines, (Talegalla Lathami, Gould,) and localities. It is, however, still abundant the native pheasant of the colonists, in the dense brushes of the Manning called ngow or ngow-00 by the abori- | and Clarence, and along the sides of gines, (Leipoa ocellata, Gould.)
the lower hills that branch off from the The first was originally described by great range into the interior ; on the Latham, under the name of the New Brezi range to the north of the LiverHolland vulture; but subsequently he pool plains, and also on the hills on removed it from among the vultures, each side of the Samoi. and placed it among the birds of the In its habits, the brush turkey is gallinaceous order to which it really gregarious, associating in small flocks,
which wander among the dense covert | labours of several; the same site appears of the brush wood; and it is shy and to me from the great size, and the entire distrustful. It runs with great facility, decomposition of the lower part, to be and from the nature of the localities it resorted to for several years in succession, frequents, easily eludes pursuit. One the birds adding a fresh supply of maof its greatest enemies is the dingo, or terials previously to laying. wild dog ; and when hard pressed by “ The mode in which the materials this ferocious beast of prey, it springs composing these mounds are accumuto the lower branch of a tree, and, by lated, is equally singular; the bird never a succession of leaps from branch to using its beak, but always grasping a branch, ascends to the top. Thew hole quantity in its foot, throwing it backflock act in concert, and having ascended wards to one common centre, and thus as high as they can, they either remain clearing the surface of the ground for perched in security, or fly to a distant a considerable distance so completely, spot, where the tangled brush wood that scarcely a leaf or a blade of grass promises a more effectual concealment. is left. They are also in the habit of resorting “ The heap being accumulated, and to the branches of trees, as a shelter time allowed for a sufficient heat to from the mid-day sun; and while thus be engendered, the eggs are deposited, reposing, they offer a sure mark to the not side by side, as is ordinarily the case, sportsman, who may kill the whole but planted at the distance of nine or flock, for they will allow a succession twelve inches from each other, and of shots to be fired, without moving, buried at nearly an arm's depth, peror being roused from their lethargy. fectly upright, with the large end upIt is by taking advantage of their mid-wards. They are covered up as they day repose, that the colonists destroy are laid, and allowed to remain until them in great numbers for the sake hatched. I have been credibly inof their flesh, which is extremely deli- formed, both by natives and settlers cate and tender, and is consequently in living near their haunts, that it is not high esteem.
unusual to obtain nearly a bushel of While wandering through the brush, eggs at one time from a single heap ; these birds utter a clucking noise ; their and as they are delicious eating, they food consists principally of berries and are eagerly sought after." various seeds; and, like our
Some of the natives assured Mr. poultry, they dust themselves in the Gould, that the females are constantly soft ground, making bare depressions in the neighbourliood of the heap, waitin the spots which they frequent. ing for the time at which the hatching
The most interesting and remarkable of the eggs takes place; and that they circumstance connected with the eco- frequently uncover and cover again the nomy of the brush turkey is, that it eggs, as if for the purpose of ascerdoes not hatch its eggs by incubation, taining their progress, or of assisting it does not sit upon them like other the young to liberate themselves from birds, not even occasionally or during their imprisonment. Others, however, the night, but forms for them an denied this, and stated that the eggs caleobion," in which they are hatched were altogether forsaken, the young without the weary duties to which other being left to liberate themselves. Una birds are called by the laws of nature. fortunately, Mr. Gould was not in the The brush turkey, says Mr. Gould, districts inhabited by these birds during “collects together an immense heap of the breeding season ; but he inclines to decaying vegetable matter, as a deposi- the latter statement, and thinks that tory for the eggs, and trusts to the from the great size of the egg, there heat engendered by the process of de- is room for the young to become more composition for the developement of the fully developed, than in ordinary cases, young. The heap, employed for this and that they are hatched capable of purpose, is collected by the birds during taking care of themselves. In confirmseveral weeks previous to the period of ation of this, he observes that, in searchlaying; it varies in size from two to ing for eggs in one of the mounds, he four cart loads, and is of a perfectly discovered the remains of a young bird, pyramidal form. The construction of apparently just excluded from the shell. the work is not the work of one pair It was clothed, not with down as is of birds, but is effected by the united | usual, but with feathers, a proof, if