350

Keeling Isds

1835 April 1st

Conferva (A) During two days before arriving at the Keeling Isds in the Indian Ocean in many parts I saw masses of flocculent matter of an extremely pale brownish green colour floating in the sea. They varied in size from half to three or four inches square in size are and were quite irregular in figure. & are coloured an extremely pale brownish green. In an opake vessel the masses could only with difficulty cannot be distinguished; but in a glass they were are very distinctly clearly visible. Under the microscope the flocculent masses are matter is seen to consist of two kinds of Confervæ, between which I am quite ignorant whether there is any connection. Minute cylindrical bodies, conical at each extremity, are involved in vast numbers in a mass of fine threads. These threads have a diameter of about 2/3000th of an inch; they possess an internal lining; they are divided at irregular & very wide intervals by transverse septa; Their length is extreme, so that I could never certainly ascertain the form of the extremity; They are all curvilinear & resemble in position a handful of hair, coiled & squeezed together. In the midst of these threads & probably connected by some viscous fluid there are innumerable cylindrical hollow transparent bodies [sketch]; each extremity (a) of which is terminated by a cone produced into the finest point.— Their diameter is tolerably

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(a) constant between 6 and 8/1000 .006 and .008 of an inch. Their length varies considerably from .04 to .06 & even sometimes to .08.— Near to the one extremity of the cylindrical part, a green septum or mass of a granular matter formed of a granular matter, and thickest in the middle, may generally to be seen.— This I believe to be is the bottom of a most delicate colourless sack, composed of a granular or pulpy matter substance which lines the exterior case, but does not extend to within the extreme conical points.

In some, a small but perfect sphære of brownish granular matter supplied the place of the septum; & I observed the curious process by which these little balls are produced. A) The pulpy matter of the internal coating suddenly grouped itself into lines, some of which assumed an obscure radiated position, then with irregular & rapid movement the lining contracted & united itself, & in a second the whole matter was collected into the most perfect little sphære, which motionless occupied the position of the sept at one end of the transparent hollow case. I can describe these motions by a simile: a bag of unequal thickness & composed of some highly elastic matter being distended by a fluid, & then such fluid being allowed to escape with some rapidity, the coats of the bag would contract & unite with similar movements.— This rapid process perhaps is a morbid one, owing to injury: certainly in many cases with such injury the process commenced.— I saw several pair of these bodies attached to each other, cone along side cone, at that end where the Septum occurs.— I do not know whether they constantly adhære in this manner when floating in the ocean.— [sketch]

351

Keeling Isds

1836 April

Meandrina 3605 The surface of this Coral is marked with sinuous convex elevated & concave depressed lines: a transverse section shows plates which form the lines of ridges & hollows.— Those which rim the latter are the thickest & best developed, & hence the mass of Coral breaks most easily in these lines. On each side there are irregular cells; & likewise on each side of those plates, which form the ridges of elevated lines, there are more regular cells. Hence we see alternate bands of different cells, on each side of different plates.— [sketch] On viewing the external surface, the lines of ridges are seen to be composed of the plate, crossed by short plates [sketch] which are either united, or nearly coincide on the line. These are the summits of the cells: but I do not understand the exact structure. At the base of the little sinuous ridges composed of the cross plates, there projects a narrow fleshy rim; this is edged by short, broard, flat, with white & rounded tips, are unequal in size, tentacula. I believe certainly they are not perforated; are soft & adhesive in their nature. They do not exactly arise in one line. The fleshy rim, from which they arise, is united with similar substance which coats in minute folds the little cross plates, & part fills up the intervening spaces.

Directly over the plate which follows the central line of the furrows, there are seated the mouths: these

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Keeling Isds

Meandrina are cylindrical, tubular, very short, diameter 1/50th of inch. (c) — the orifice is in folds in centre of tubular fleshy projection [sketch]. In the space of 1/2 an inch there is about 8-10 mouths, & on each side at the base of the ridges about 28-30 tentacula. This gives a proportion of from 6-7 tentacula to each mouth, but in other parts the proportion was 8 or 10 to a mouth.— Beneath the spot of the mouth, the rays or sides of the cells unite sometimes one on each side, & sometimes more, to the central plate: On touching the tentacula, the rim is partly contracted, & together with tentacula is drawn within the folds of the little cross plates: These rims & their tentacula can likewise be partly covered drawn together so as to cover the mouths.— There is no division to show which tentacula belong to which mouth. (a) The tentacula on opposite sides of the same ridge must belong to different lines of mouths.— On injuring cutting off the mouth, a white delicate folded membrane is protruded, precisely similar to what is seen in Caryophillia.—

In splitting the coral, it generally breaks in a line with a furrow: in the two pieces, one will have the smooth plate attached to it, the other will show expose the cells which bordered on one side.

[Annotated sketch in margin]

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(a) The fleshy matter is united in the folds across the ridge.—

(b) The plate is crenated on its superior margin.—

(c) The mouths do not project so high as the line of Tentacula.—

 

353

Keeling Isds

1835 April.

Meandrina (3605) the principal plate.— In this longitudinal section, the living part colored pale purplish brown of the great globular mass is seen only to extend to .2 in depth, beneath this .1 deep in stained green, but dead & the whole central part entirely dead.— The upper & living row of cells are occupied, on each side of the plate, with the delicate folded membrane, which protrude out directly after splitting the coral.— As the mouth of the animal is placed directly over the plate, & where the sides of two & occasionally more cells unite, the folds depend into as many cells.— This structure is analogous to Caryophillia, where the axis of the stem is divided into many compartments. Although the greater number, not all the cells are so occupied, some being empty: this is probably connected with the upward growth of the Coral, & agrees with the fact that the septa or bottom of the cells are not all placed in the same line.— Although the globe mass of Coral easily divides into sinuous layers each of which composes a ridge; yet the fleshy matter is united over the whole surface.— In its growth it has frequently surrounded & enclosed branches

354

Keeling Isds

1835 April

Meandrina of the stony Corals.— Such spots are centres from whence the furrows & ridges diverge. The surface of the Coral is very slimy.— The mass lies scarcely or not at all attached to a sandy bottom in the shoal lagoon.— There can be no doubt but what this animal belongs to the same family as Actinia & Caryophillia.—

Madrepora (3560) This stony branching elegant Coral is very abundant in the shallow still waters of the Lagoon: it lives from the shoalest parts, which are always covered by water, to a depth certainly of 18 ft & perhaps more. Its color is nearly white or pale brown. The orifice of the cells is either nearly simple, or protected by a strong hood: the polypus is similar in both.— The upper extremity or mouth of the Polypus is closely attached to the edge of orifice: it cannot be protruded, nor drawn back out of sight; it consists of narrow, fleshy lip, which is divided into 12 tentacula or subdivisions of the lip. These tentacula are very short & minute [sketch], are flattened vertically, are brown colored, tipped with white. The animal possesses very little irritability, on being pricked the mouth is folded or contracted into an elongated figure [sketch] & partially drawn back. The body of the Polypus fills up the cell, is so excessively

355

Keeling Isds

1835 April

Madrepora (3560) delicate, transparent & adhæsive that I in vain tried to examine its structure. I could see a sort of abdominal sack, outside of which & attached to the side of this there were intestinal folds of a whitish color. These when separated from the body possessed a sort of peristaltic motion.—

3584 I examined the Madrepora (3584) also common in the lagoon & found the same sort of Polypus, & from a shorter examination I believe such will be likewise found in kinds (3612) ( )

Madrepora 3586 This foliaceous Madrepora is of a pale brownish purple color. is extremely slimy. is abundant in from 3-7 fathoms water in the lagoon. When alive, from each orifice a minute corella like lip is protruded which folds over & lies flat around the orifice. is colored "Lake red". This lip is marked by about 12 rays, but is not absolutely divided into so many tentacula. The animal possesses little irritability. the lip can be with drawn within, but to no depth in the orifice.— In the centre of this upper extremity, there is a small simple aperture or mouth. between this mouth & the lip there are 6 small brown points.— The whole resembled a beautiful microscopical flower.— The body, as well as entire

356

Keeling Isds

1835 April

Madrepora 3586 upper extremity is colored lake red. is likewise pulpy, adhæsive, delicate & attached to the Coral.— In the body, I could trace intestinal like compartments, & on one side folds of the main sack, folds of colourless intestine: each fold appears to be a loop of the intestine, the two parts joined by a granular substance. A piece of single intestine being detached revolved in the direction of the space into which it was folded.

3587 There is another species4 (3587) found in same situation, the polypus of which is I believe of the same structure. Here however the lip is white. These foliaceous Corals appear to have an intimate connection with the stony branching Madrepores.

Millepora 1419 spirits of W: I examined with considerable care two species, taking specimens from different places on successive days of this genus, & utterly failed of perceiving anything like a Polypus, yet from the structure of the Coral I must suppose such are present.

3583 3609 Millepora (3583) (a) Millepora (3583) is branched & colored "Sienna yellow & Wood brown". it grows in from 0-12 Fathom water on the outer reefs. The coral consists of stony reticulations; from the axis of the branches vessels cells radiate through this substance to the outside.

357

Keeling Isds

1835 April

Millepora (3583) It is divided by transverse septa into cells. the orifice of the terminal one is seen outside as a white spot.—

In parts of the older branches the orifices are not quite of equal size, the smaller ones being arranged around a central larger one.— In a section of the Coral, many of these vessels will be seen to be covered up & not continued to the surface.— Towards the I examined a considerable number of the cells when the Coral was broken & could find nothing; but at last in one specimen, from several of the cells, with a broken bent needle I removed a minute portion of a gelatino-membranous substance; in this with a high power I could trace no structure. Can this be part of a Polypus? The whole Coral is of a harsh feel & not perceptibly slimy, by gently scraping the surface & particularly the whiter terminal extremities of the branches: with a high power, a most delicate transparent membrane (without any structure) will be found. beneath this is a most thin layer of pulpy matter in which the rounded & loosely attached extremities of the stony reticulations are imbedded. It would appear that

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(a) I saw this coral at the Isle of France forming great bushes 2 ft: high.— not infrequently it coats any foreign body in place of forming distinct branches: of which specimen (3634) is an instance

358

Keeling Isds

1835 April

Millepora (3583) these reticulations increase, by the apposition of minute stony sphæres.— In the matter thus scraped off from several parts of one specimen, I found numerous little oval transparent balls, having diameter of about 1/1000th of inch. These are attached by one end to most delicate strength filaments, which commonly are divided dichotomously.— These filaments under a 1/20 lens where injured are seen to consist of a spiral fibre, which when stretched is partly unrolled.— [sketch] I at first thought it had some connection with the Coral, but now believe it to be a most minute microscopical parasitical plant or animal.—

(3610) 3611 The second series of Millepora grows in strong vertical plates, which frequently intersect each other & so form a coarse honeycombed mass. In such masses the outer parts alone of the plates are alive. This Coral flourishes in the outer part of the reef where the sea violently breaks. Its color is a mixture of "Wax & Sulphur Yellow", the former being the prevailing tint in the lower & older parts, as the bright yellow is in the upper parts of the plates. The structure & superficial nature of this Coral precisely resembles the foregoing

359

Keeling Isds

1835 April

Millepora ( ) species. I could not perceive any trace even of a Polypus in the terminal cell.— I see the branches grow by concentric additions: [sketch] & that the lines of cells on vessels do not occur near to the extremities: therefore the growth of the Coral must be a process quite distinct from the agency of the Polypi, if such there be.— The orifices of the cells in this species are seen to be often very different sizes, the smaller ones being grouped around a larger central one.—

In Both these species agree in having very little or rather no slimy matter on their surface; but yet possess a strong & disagreeable odor.— they likewise agree in the very remarkable property, hitherto I believe unnoticed in such productions, of producing on contact a stinging sensation. Mr Liesk first observed this fact by accident in the plate kind, & I find it as strong or stronger in the branched sort.— The power appears to vary: generally speaking on pressing or rubbing a fragment on the tender skin of the face or arm, a prickling sensation will be felt after an interval of a second, & which lasts for a very short time. But on rapidly touching with the specimen (3609) of the

360

Keeling Isds

1835 April

Millepora branching kind the side of my face, the pain was instantaneous, but increased, as usual, after a very short interval; the sensation continued strong for a few minutes, but was perceptible half an hour afterwards. The sensation was as bad as that of the sting of a Nettle, but more resembled that produced by the Physa.— On touching the tender skin of the arm, red spots were produced, & which had the appearance, if the stimulant had been a little stronger, of producing watery pustules. With respect to the nature of these Milleporæ, I cannot help suspecting that their nature is allied to Corallina rather than to Polypiferous Corals.— I am led to this idea from not being able to discover any trace of an organized Polypus in the cells; their position with respect to extremities of branches; their size varying & their method of grouping; all which facts would better agree with the idea that the cell is the seat where the Ovum is produced.— Their manner of growth & the absence of slime is analogous to the Corallinas.—

361

Keeling Isds

1835 April

Actinia (1415) The specimens which I found were adhæring to old shells, which were inhabited by hermit crabs: they lay beneath large stones on the outer reef.— The flower (or upper surface) has a general pale, dull "Crimson red" color. it is regularly radiated with white from the mouth to outer margin.— The tentacula are numerous & placed in many rows; the innermost are longest & they gradually decrease in length to outer row: each tentaculum tapers towards its extremity. central mouth "tile red".— where contracted, conical pins body, whole flower concealed: when expanded semitransparent & delicate. External surface colored "purplish red", irregularly mottled with white.— The mouth internally is formed by four longitudinal ribs or folds on each side, & in each corner two more smaller & obscure projections, making together 12.— About a tenth of inch above the face of the body there is a ring of 24 conical little paps which have orifices. These orifices are closed when the body is contracted. The paps (a) or glands are white. The animal has the remarkable power when irritated

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(a) of emitting from its mouth & 24 glands or pores, bunches of viscous threads. These threads are colored "Peach blossom & Aurora Red". they can be drawn out, when in contact with any object to the length of some inches, & are emitted with considerable force.— they are not at all strong. The pores near the part most irritated only at any one time ejected this substance. The animal having been kept for a day still retained this power.— Within the body in the basal parts, large quantities of these red threads are laid.— I know not whether their nature or use.—

362

Keeling Isds

1835 April

Crab 1428 Copied These monstrous crabs inhabit in numbers low strips of dry coral land; they live entirely on the fruit of the Cocoa nut tree. Mr Liesk informs me he has often seen them tearing fibre by fibre, with their strong forceps, the husk of the nut. This process they always perform at the extremity, where the three eyes are situated. By constant hammering the eye shell in that soft part is broken in & then by the aid of their narrow posterior pincers the food is extracted. I think this is as curious a piece of adaptation & instinct as I ever heard of. These Crabs are diurnal in their habits: they live in burrows, which frequently lie at the foot of trees. Within the cavity they collect a pile, sometimes as much as a large bag full, of the picked fibres of the husk & on this they seat rest.— At night they are said to travel to the sea: there also their young are hand hatched, & during the early part of their life they remain & probably feed on the beach. Their flesh is very good food: in the tail of a large one there is a lump of

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(a) fat, which when melted gives a bottle full of Oil. They are exceedingly strong.— The back is coloured dull brick red; the under side of body & legs is blue, but the upper side of legs clouded with dull red.— In the "Voyage par un Officier du Roi" to the Isle of France, there is an account of a Crab which lives on Cocoa nuts in a small Isd North of Madagascar; probably it is the same animal, but the account is very imperfect.—

NB. These Crabs are in a Cask with a black cross at one end.—

NB. Mr Liesk informs me that the Crabs with swimming plate to posterior claw employ this tool in excavating burrows in the fine sand or mud & that he has repeatedly witnessed this process.—