Haliotis being furnished with tubes or spiracles well known as so many passages for a syphon; while Stomatella and Stomatia, which in other respects so much resemble it, have none.

And yet a mere breathing hole would scarcely require to be protected by a tubular process. But there may be attached to the neck of the animal of Spiraculum, an apparatus similar to that described by LAMARCK as possessed by the genus Valvata of his Péristomiens;-" un filet branchial et tentaculiforme au côté droit du cou, et quelque-fois une branchie en plumet et contractile, qu'il fait sailler hors de sa cavité:" or a projecting syphon, such as carries on the respiration of the second section of the Trachelipoda. Thus there would be an animal breathing air yet furnished with the apparatus, or a modification of the apparatus of one inhabiting and breathing only water, and consequently occupying an intermediate place in the chain of affinity, and forming an inosculation between the two. If so LAMARCK might have adduced it, had it been known to him, as another fact, strongly confirmative of his celebrated idea of the gradual perfection of the animal form. His remarks on the subject are so apposite, that they deserve to be quoted entire. A mesure que," says LAMARCK, "les animaux se repandirent partout de proche en proche, il parait que ceux des trachelipodes fluviatiles que habitèrent les eaux qui ont peu de profondeur, comme celles des petites rivières des étangs, et des marais, que sont exposées à tarir, furent souvent réduits à vivre dans une vase plus au moins desséchée. Ils se trouverent donc forcés à s'habituer à l'air, á le respirer. Or cette habitude ayant modifié leurs branchies, comme celles des colimacés, est devenu pour eux une nécessité; en sorte que quoique vivant dans l'eau ils sont maintenant obligés de venir de temps en temps à sa surface pour y respirer l'air libre." If any change of this kind ever did take place, it may perhaps be found at some future time, when physiological investigations are better understood than at present, that these animals are able to breathe both air and water; and further, should the above conjecture as to the respiratory apparatus of Spiraculum prove to be correct, there will be another link of union between the second section of Colimaceés and the Péristomiens beside that of the Lymnéens.

Genus, Spiraculum. Species, Hispidum. Specific Characters. Animal unknown.

Shell white, subdiaphonous, upper surface of the body whorl slightly patched with rufous. Epidermis dark-brown, covered with short bristly hairs, which at the outer and under side of the whorl are placed thickly together, giving an appearance to the shell of its being zoned with three narrow dark lines; whorls five, breathing tube one line

in length, conical, compressed, pointing backward and inward; mouth Diameter one inch. circular, lip thickened and reflected.

Operculum corneous, formed of several spiral layers, deeply cupped at the outer surface, and plano-convex at the inner.

All the specimens of this collection have the mouth dilated at the upper margin into a surface more or less flat, or concave, or formed like a sinus. But in the above description it is assumed to be circular, because it is almost of that form in the more advanced specimens, from the dilatation having become a well-marked sinus, and in one or two nearly formed into a tube. In a smaller species also, in the collection, the tube is actually formed in this manner, being at first a dilatation, then a sinus, as fresh shelly matter is deposited, and finally a tube and in proof of this, a series of specimens may be seen in the collection, in which are gradual changes from a slight dilatation of the upper margin of the aperture, to the perfect tube and circular reflected lip.

2.-Spiraculum Parvum.

Shell white, subdiaphonous, zoned with a dark-brown line along the circumference of the whorl, striated above with brown zig-zag striæ, and less distinctly so below. Shelly spiracle or breathing tube situated near to the mouth. Mouth perfectly circular; lip thickened and reflected, umbilicus largely dilated, upper surface plano-convex, , almost flat. Diameter of an inch.

Operculum unknown, supposed to resemble that of S. Hispidum. Epidermis dark-brown.

3. The shell described by Mr. BENSON under the name of Pterocyclos rupestris.

It is thus ascertained that there are at least three species of this interesting genus, and it is hoped that the reasons detailed above are an excuse sufficient for changing the name bestowed upon it by Mr. BENSON; at all events, it has been done from a sincere conviction of its necessity, and not from any spirit of innovation.

VIII. On the Kukumb ka Tel, or Concrete Oil of the Wild Mangosteen. To the Editor of the Journal of the Asiatic Society.

SIR,

The motto on the title page of your Journal induces me to send you a few remarks on a substance which I have reason to think possesses some very peculiar properties, which entitle it to be made the subject of experimental investigation.

This substance is the Kukumb ka Tel of the natives of this part of the country, or the concrete oil of the wild mangosteen, a tree which is common in some parts of the Southern Konkan. I am not aware, whether any or what difference, further than may be induced by cultivation, exists between the above and the much-extolled mangosteen of the Straits. The fruit ripens in April and May; is small, and of a flattened globular form. The rind or shell is about th of an inch in thickness, of a deep crimson colour, and intense acidity. Within this, but without adhering to it, is contained a pulpy mass, in which the seeds are imbedded. The oil is extracted from the seeds by boiling. They are first exposed for some days in the sun to dry, and then pounded and boiled in water: the oil collects on the surface, and on cooling concretes into a solid cake. When purified from extraneous matter, the product is of a rather brittle quality; of a pale yellowish hue, the shade inclining to green; exceedingly mild and bland to the taste, melting in the mouth like butter, and impressing a sensation of cold on the tongue, not unlike what is experienced on allowing a particle of nitre to dissolve on the tongue.

From several experiments on this substance with the thermometer I have been led to the conclusion that in passing from the coucrete to a fluid state, and conversely from a fluid to the concrete form, it is guided by some peculiar law, in consequence of which it has two distinct temperatures, removed from each other by several degrees, at which it passes respectively from one state into the other. I need not here detail the numerous trials I made on it, as the general result was the same in all. My first object was to ascertain the temperature at which it congealed or passed into the concrete form. This from repeated trials I invariably found to be about 90°. In one instance, having brought the substance into a perfect state of fluidity, I placed it in an oven with a temperature at first above 100°, but allowed gradually to descend. When the Thermometer, which was placed beside it, indicated 88°, I expected to have found it congealed; but perceiving that it still retained its fluidity, I took it out and plunged the bulb of the thermometer into it. The thermometer immediately rose to 94°, at which it continued for some minutes, (the external air at the time being 72o,) and then gradually descended to 90°, at which it became stationary for some minutes before the substance began to lose its fluidity and transparency : then without indicating any change of temperature, the process of congealing commenced at the sides of the vessel, the opaque cloud slowly creeping in towards the centre, and the thermometer all the while remaining at 09°.

The result of various trials satisfied me, that this substance could not be brought to congeal at a higher temperature than 90°; but in experimenting on it in the solid state, that temperature was found quite insufficient, by several degrees, again to liquify it. The following is a brief statement of the result of several trials to ascertain its melting point. It was subjected to a gradually increasing temperature, commencing from 90°, with considerable intervals between every higher accession of temperature, to allow time for the effect which was capable of being produced on it. From 90 to 100°, the effect was merely to soften it: at 102°, it still preserved its cohesion, but the consistency was that of butter in warm weather: at 106 part began to separate in a semifluid state, transparent at the edge and opaque in the centre; and a few minute globules were separately observed in a perfectly fluid state. Every fresh accession of temperature had of course the effect of bringing it more and more towards a state of fluidity; but up to 116°, there was still observable a partial opacity, and it was only when the temperature had reached about 120°, that it could be said to have attained perfect fluidity and transparency*.

Another peculiarity in this substance is the irregular form its surface is thrown into in the act of concreting. Nor does it appear capable of being prevented by any management, or by conducting the process in the most gradual and gentle manner. But the effect may be considerably increased by exposing it in a fluid state to the sudden application of a cooling medium. Having a stratum of the fluid oil at 120°, floating on water in a small cup, I suddenly exposed it to the chilling influence of a slight drizzling rain and sharp breeze, the temperature of the air being 70°: the rapid abstraction of heat soon caused the congealing process to commence, and the entire surface shot up into a series of prismatic or columnar masses, about 4th inch in height, and separated from each other by small intervals. This effect took place some time before the substance became perfectly opaque; and while in this state, it had the appearance of a crystallized body, in an intermediate state between opacity and transparency, of which we have a familiar instance in a piece of loaf-sugar dipped in water.

The concrete oil of the mangosteen might I apprehend be advantageously introduced into pharmaceutical preparations. It is used by the natives as a healing application. I have noticed among its sensible properties, that it impresses a sensation of cold on the tongue; from which it would appear, that it powerfully absorbs heat, as several salts do in the act of dissolving. It is easy to conceive that this * The same peculiarity is observable, more or less, in all the concrete oils: it is probably owing to their bad conducting power.-ED.

property may often be of great service in wounds or sores, accompanied with inflammation, which it is desirable to abate.

The quantity of the concrete oil that may be obtained from the seeds may be taken at about one-tenth. From lb. avoirdupois or 3,500 grs. of the seeds, I obtained 360 grs. of the concrete oil in a moderately pure state. The above is somewhat more than 1-10th; and with better management, the product might perhaps be greater. It requires however long-continued boiling to extract it, and it is still more tedious to purify it from the fibrous matter of the seeds.

Western Ghauts, 25th September, 1833.

N. N. L.

IX.-Note on the Coal discovered at Khyúk Phyú, in the Arracan District. [Read 30th October, 1833.]

Lieut. FOLEY has been most active in investigating the mineral resources of this almost impenetrable country, where swamps and jungles of the worst description render it hazardous to reside, while they hide for the most part the features by which a geologist is enabled to direct his researches.

The seam of coal discovered at Syneg Kyong, as shewn in Captain MARGRAVE'S sketch, Plate XIX. Fig. 3. is most conveniently situated for exportation, should it turn out abundant, and of good quality. The Oong Kyong* creek (reed-nala) falls into Khyúk Phyú harbour, just beyond the anchorage of the ships, and the nala itself is deep enough for all small vessels. The following description of the place is extracted from a note by Captain MARGRAVE.

stone.

The hill towards the creek describes the segment of a circle, is very steep, and no more I think than 50 or 60 feet from the sea level; the soil is sand and clay, variously proportioned, of grey, yellow, and sometimes a reddish colour, resting apparently on coarse grey sandIt is isolated by the spring-tide, whose fall leaves exposed a flat level ledge of rock, (extending some 70 yards or more N. W. of the hill,) composed of grey sandstone with a brick-red tinge on the surface, particularly near the edges of the blocks and fissures. This sandstone seemed to me to disappear under the hill, for on the other side I found precisely similar stone in fragments, but not the same perfectly horizontal bed. The vein of coal runs about E. and W. (along the line DB) across the southern part of the ledge; at B is the pit sunk by Lieut. FOLEY, 3 or 4 feet deep, on a former visit: at A and C are the smaller excavations whence came the best specimens of ore and coal. The vein is not straight, however, but rather serpentine, or

* In the plate this has been called Syneg-kyong by mistake.-ED.