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breast, belly, thighs, covert-feathers withinside the wings and under the tail, are white: the top and hinder part of the head is black. The lower part of the neck behind, and the back are of a blueish ash or slate-colour, with a mixture of blackish or dusky: the upper sides of the wings and tail are of a blackish or dusky colour: the tips of the covert of the wings are white; the tips of the middlemost or shortest of the quills are also white, and form white transverse bars across the wings. Two or three of the middle quills are wholly white, and all of them have their inner webs white toward their bottoms. It has 12 feathers with white. The
in the tail; the outermost of which, on each side, is edged covert-feathers on the rump, or upper side of the tail, are dusky and white. The legs are bare of feathers above the knees (as they are in most birds that wade in shallow waters,) and of an ash colour.
XXXII. Description of Several Small Marine Animals, by Job Baster, M.D. F. R. S. p. 258.
Dr. Baster's arguments, relative to the supposed vegetable nature of corallines, being recapitulated in Mr. Ellis's answer, it is unnecessary to preserve that part of the present paper. We shall therefore translate only the part in which he describes various small marine animals; some allied to the polype tribe, and others of different families.
If the sea water round our coasts be moved by night, either by throwing a stone into it, or by a stick, it exhibits innumerable fiery sparks, which are no other than minute shining animalcules, requiring a good microscope to show them distinctly. In order to collect these animalcules in sufficient plenty, the way is to take a quantity of sea-water in which they abound, and to strain it through a filtering paper, till only the quantity of about half an ounce, or less, remains on the paper: of this water a small drop, placed in a concave glass, and viewed by a microscope of considerable power, will exhibit them swimming very briskly about. Dr. B. observed three species, which are represented from the life at plate 5. fig. 22.
But the sea nourishes other animals in which this lucid quality exists, and of which some that were found in corallines are shown, fig. 25, 26, 28, 29; but these he does not particularize, since several authors have written concerning them.
If a large plant of coralline fresh taken from the sea, be placed in a Chinadish, the bottom of which is of a deep blue colour, in a sufficient quantity of very clear and filtered sea-water, and its branches be carefully expanded, and viewed by a magnifier, one may often see a wood, as it were, in which a great many animals live, exclusive of various kinds of polypes infixed in the branches and extending their arms: there are also still several others, especially in the
lower parts of the corallines, have grown on oysters, which move about here and there, and perhaps serve by way of food for the oyster when it opens. Thus on the 23d of October, 1756, I took an oyster on which grew a large plant of coralline (fig. 15), in which, besides three different species of polypes, I found six different kinds of insects. The first was a worm, (fig. 22.) the head of which was furnished with six larger and two smaller horns. Another was a very small long-legged spider, much resembling the kind called by the French le fancheur, and of very slow motion. (fig. 30.) A third was a worm, as at fig. 27, which I lost while engaged in drawing it. A fourth, fifth, and sixth (fig. 32.) were not visible without a powerful microscope. Of these the animal at letter c is of a wonderful structure.
Examining in this manner different oysters and corallines, I saw several more such wonderful insects, the delineations of which are given at figures 26, 27, 28, 29, 31. On the 16th of the same month of October, several very small corallines were brought me, which had been taken from the surface of a buoy in these, though often examined with great attention, I could not discover any polypes, but two other very wonderful animals.
Of these, which the letter A, fig. 23 exhibits, there were thousands, either creeping or swimming with an extreme brisk motion: they held or adhered to the small branches of the coralline with their 6 hinder feet, in the manner of the caterpillars called geometræ, sending themselves up and down in a wonderful manner, leaping with great activity from branch to branch. Among these were some few of a larger size, which are represented both in their natural size, and magnified. (see fig. 23, band c.) Another animal, fig. 24, was not less surprizing; but an idea of all these animals will be better obtained by an inspection of the figure, than from a prolix verbal description." But if, says Dr. B. "I should
attempt to delineate all the marine animals which I have discovered in dif"ferent corallines, I should undertake a work of infinite labour; for their num"ber and diversity are such as to exceed my powers."
"These observations however may, I hope, prove sufficient to demonstrate "that corallines are not the work or fabric of polypes, but that they merely "serve as a habitation and refuge, as well as food, to these and a great many "other small marine animals."
Explanation of the plate v.-Fig. 1. shows a plant of coralline called corallina muscosa, sive muscus marinus tenui capillo spermophoros.-Fig. 2. Corallina ramulis dichotomis teneris capillaribus rubentį– bus. Fig. 3. A young plant of the corallina tubularia laryngi similis.-Fig. 4. Two species, a, b, (same as fig. 1 and 2), and c. eschara papyracea utrinque cellulifera, growing to one base, as often happens on buoys.-Fig. 5. A small branch of red coralline, which I kept for some weeks in seawater, often renewed, during which time the small branches a, a, grew very considerably, and others, b, b, sprouted forth.-Fig. 6. Part of an oyster-shell, in which, besides certain green fila
ments, two polypes, a, a, may be seen.-Fig. 7. Cancer arachnoides, on which were seated two species of polypes. A single or simple one at a, and many, inhabiting cells, at b.-Fig. 8. An animal called narsgat, which adheres to the wood of floodgates and ships: on this grew a small plant of coralline, in which I could not perceive any polypes; but several, b, b, were seated on the animal itself.
N. B. The delineator has represented the tails of these, and the polypes of the preceding figure too long, in order that they might come the better into view.
Fig. 9. A branch of red coralline in its natural size.-Fig. 10. The same viewed by the microscope, and in which three species of polypes may be seen.—a, b, Two different species, fixed by the tail or hinder part of the body to the coralline.-c. A third species, inhabiting the cells.-d. A dead polype.—e. The cells of the polypes.-Fig. 11. A plant of the corallina tubularia laryngi similis, în its natural size.-Fig. 12. A very large branch of this coralline viewed by the microscope, in which are discovered 5 different polypes.—a. The first and largest species, which I name the scarlet polype, and which is shewn at fig. 17, still more strongly magnified.-b. The same sort, but a smaller polype.-c. The third, which is the same as that at fig. 10, letter b.-d. The 4th, which is the same as letter c, fig. 10.-e. The 5th and least kind, and which is represented again at fig. 16, as well as very highly magnified.-f. The cells which the fourth species inhabits.— Fig. 13. Corallina erecta pennata, denticulis alternis cauli appressis: in this there were no polypes, unless in the cellules affixed here and there about the trunk.-b. The shells which are shewn magnified at B, fig. 14.-c. Eschara millepora minima crustacea cellulis tubiformibus, serving as a lodgement to animals, and magnified at c.-Fig. 14. Corallina abietis forma: this I received in December; its branches were beset with vesicles or eggs, a, a, disposed by pairs in regular order.—a. One of these vesicles or eggs shown by the microscope, b, shells, and c, eschara minima, as in the former figure, where they are represented magnified at в, c, d, d. Two brown corpuscles, which being viewed by the microscope, represent a nidus of worms, D.-Fig. 15. Corallina pennata et siliquata, taken from an oyster-shell: in this, besides 3 species of polypes, a, a, b, B. (the same as at fig. 10,) c, c, six other insects were observable, which are represented in fig. 25, 30, 32.-Fig. 16. A kind of very small branched polypes, allied to the polypes a bouquet of fresh water. —▲. A polype of this kind adhering to a green marine conferva, and hardly visible to the naked eye.-B. The same viewed by a common magnifier, and at c, by a microscope of considerable power.-Fig. 17. The scarlet polype, represented both in its natural size, and magnified at fig. 11 and 12, and here shewn very highly magnified.-A. This polype, with its arms expanded, waiting for its prey.-B. The same animal, in the act of contracting its arms when catching its prey.-a. The larger inferior arms, 16, 18, or 20 in number.-b. The upper shorter arms, 12, 14, or 16 in number.-c. The upper, pear-shaped part of the body, affixed to the lower.-d. The lower compressed part of the body.-e. The place where the polype adheres to the coralline.-c. The same polype seen in front, with the body contracted into a globular form, which is more visible in the larger kind, figured at 19, 20, 21.-Fig. 18. A similar scarlet polype, larger than the rest, from the body of which (where the parts c and d are joined) 8 small branches grew, which on their tips had two or three globules with a red spot on the middle of each, and which I in vain hoped would have grown into young polypes.-a. The longer inferior arms of this polype.-b. The upper shorter arms.-c. This seems to be the mouth, in the middle of the pear-shaped body of the polype.-Fig. 19. A larger kind, as it should seem, of polypes, called klapkonten, seated on oyster-shells, and which, when irritated, withdraws its arms entirely into its body.-Fig. 20. The `same polype, with its body extended, spreading its arms.-Fig. 21. The same contracting itself, having caught its prey.-22. Three species of luminous animalcules represented highly magnified in a . small drop of sea-water. Fig. 23. A wonderful animal found on corallines taken from buoys.— A. Of this kind were hundreds.-B. Ten or twelve were of this size.-c. The same animal seen through a microscope.-a. antenna.-b. the first pair of arms or legs.-c. The second pair.
d. The third or largest pair,-e, e, e, e. Four egg-shaped bodies, which the animal moved when swiming.-f, f, f, f, f, f. The six hinder legs or feet, with which it held a branch of the coralline, and was thus enabled to bend itself about in all directions.-g. The tail, at the end of which is the vent.—h. The eyes.-Fig. 24. Another animal found on the same corallines.-A. The animal in a prone situation.-B. In a supine situation.-c. Considerably magnified.-Fig. 25, 26, 27, 28, 29, 30, 31, 32 exhibit certain luminous and other animalcules found in different corallines magnified.—The animalcule c, fig. 32, was of a highly singular appearance, and had a great many
XXXIII. Remarks on Dr. Job Baster's Observationes de Corallinis, &c. in the foregoing Article. By Mr. John Ellis, F. R. S. p. 280.
Dr. Baster endeavours to prove, that corallines are not of an animal, but a vegetable nature; and has brought many arguments to support his system; which to gentlemen not well acquainted with the subject may appear plausible. It is to be wished that the Doctor had read and examined thoroughly what has been lately written on the subject.
His first argument is, that because he does not find as many polypes in the corallines adhering to ships, flood-gates, and buoys, as in deep water on oysters, muscles, and rocks, therefore he concludes that corallines are not formed by polypes. In answer to this, let us examine the pliable structure of these bodies, and how wisely nature has defended such tender substances with a tough thin membranaceous covering, and we shall find that the sea is calm enough often near the surface to give them leave to grow, even in the strongest currents: though doubtless they are more liable to be destroyed in such agitated situations than in the calm depths of the sea.
His 2d argument is, that finding polypes are not equally dispersed over the whole plant, how can they form it? and gives an example, pl. 5, fig. 13, of a coralline that is incrusted with many other corallines or polypes on the stem, but has none on the branches. Here we plainly see the mistake: the Doctor looks for the tender part of the polype on the surface of the coralline, considering it as a plant; and indeed, if this was the case, he ought so to do; but he never once takes notice of the internal hollow structure of the stem, branches, and denticles of those bodies, to inform us whether he found an animal in those parts or not. This material point he seems not to have thought on; which is really the true point in controversy at present among gentlemen who have not examined these bodies recent in sea-water.
His 3d argument is, that almost always one and the same coralline plant cherishes polypes of different kinds; and refers us to fig. 10 and 12. In fig. 10 he gives an elegant painting of a geniculated red conferva for a coralline, surrounded, as is very common, by many species of small corallines and escharas. And in fig. 12 he gives a drawing of one of the tubular corallines, with the head
of the animal at the top of it; the stem of this is incrusted with 4 different corallines and escharas, like the conferva fig. 10; and then he asks, which of these 5 polypes made the tubular coralline? To give him some proof of the animal nature of this coralline, let him consult Ray's Synopsis, ed. 3, p. 34, n. 4, and there he will find one of this species, called adianti aurei minimi facie planta marina, noticed so long ago as the year 1713, by Dr. Lloyd, as a zoophyte, from its stem or tube's being full of a thick reddish liquor, rather resembling blood than the juice of a plant; which on pressing the stem communicated with the little head at top.
His 4th argument is, that as upon one and the same coralline plant you shall find different kinds of polypes; so in different species of coralline the same polypes: and to confirm this, he quotes my Essay on Corallines; where it is remarked, that the polypes in the denticles of the setaceous or bristly coralline, No 16, appear to be like those that are on the lobster's-horn coralline, N° 19. And to illustrate this, he observes that bees and wasps always build their cells invariably the same; and that therefore these 2 corallines should be the same.
But he also takes this matter wrong: he has considered, in all his observations, the heads of those parts of the polype in which are the mouths, arms, or tentacula, which appear coming out of the cups, denticles, and at the ends of the tubes of the corallines, as so many whole and entire animals, without ever observing that the body of the animal is contained in the tubular part of the root, stem, and branches; and that these differ from each other widely both in size and shape, as he may plainly see in the 2 corallines he has instanced. Further, his comparison to bees and wasps, and their cells, is not conclusive: for these ramified, hollow, and denticulated bodies, called corallines, which we so frequently find dead on our shores, are properly skins of certain marine polypes, and not nests, as those constructed by these little winged animals are. And yet we find as great a regularity in the same species of these corallines, as when we compare 2 oak-trees to one another, or 2 of Mr. Trembley's branched freshwater polypes to one another.
His 5th argument is, that if corallines were formed by polypes, neither the polypes, nor even their cells, would ever fix on living animals, or any other bodies. Here we may observe, that the consequence he draws does not follow: for corallines may be formed or produced by certain species of polypes, and yet polypes of another species may be found adhering to other bodies, and even to animal bodies.
By his 6th argument he endeavours to prove, that the vesicles which are found. in regular rows on the sea-fir coralline in winter, fig. 14, do not belong to it; and are no more than the eggs of some sea-insect deposited on it, of which there may be a great variety. But to convince him of his mistake, let him take off