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assimilate it to the parasitical sorts of these plants. Fugitive negroes sometimes subsist on it, as do also deer and wood-rats, when it grows sufficiently near the surface to attract their attention.

An Account of Rhizomorpha Medullaris, a new British Fungus. By Sir James Edward Smith, M.D. — This nondescript rhizomorpha was first observed by Mr. Bainbrigge, house-surgeon to the Derby Infirmary, who thus describes it:

• The reservoir in which it was found is a kind of a circular cellar, with an opening at the top. It is situated in the shrubbery, and contains water to supply the baths, which is conveyed by deaden pipes. As the water is sent by a forcing-pump, a piece of timber was fixed across the upper part to support a perpendicular pipe that admitted the water. From this timber, which was deal, and not in the least decayed, the plant hung, and as the depth of the water varied, a greater or less quantity Hoated on the surface. I believe the whole of it would be seldom immersed; but the wood and every part of the plant would be always wet, in consequence of the water going in with considerable force. I saw the joiner measure the fungus immediately on our getting it out; and he says the length was twelve feet. This I have quite forgotten ; but am inclined to think him mistaken. The plant had a beautiful appearance in the water, from the fibres diverging in every direction, and its whiteness, which was lost when it became dry. The extremities were peculiarly brittle. Even the agitation of the water broke off large quantities. This produced great incon. venience, and several attempts were made to destroy the plant, by clearing it away ; which not succeeding, the timber was, at length, removed. Oak has been substituted, smeared with tar, pitch, and tallow, which has hitherto had the desired effect. The old beam has been used for other purposes."

Combining this account with the drawing of portions of the plant, and the President's remarks, no doubt can remain of its proper station in the system, or of its extreme rarity.

A Century of Insects, including several new Genera described. from his Cabinet. By the Reverend William Kirby, M.A. F.R.S. and L.S. - Were we to convey to our readers an adequate idea of the value of this new acquisition to our stores of entomological knowlege, we must transcribe the paper itself. Many of the species which are characterized have been procured from Brazil, and several from Australasia, and other quarters of the globe. To have accurately discriminated so many little strangers is a task of no trifling import: but the manners and habits of most of them remain to be unfolded.

A Description of several new Species of Insects, collected in New Holland by Robert Brown, Esg. F.R.S. Lib. Linn. Soc. S 3

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By the Reverend William Kirby. - These species are designated Buprestis cruentata, tricolor, phæorhæa, rufipennis, decemmaculata, cuprifera, cupriceps, and fissiceps ; Rhipicera femorata ; Scarabeus juba, and Australusiæ ; Trov spurins ; Melolontha sericea ; Cetonia atropunctata, Brownii, and brunnipes ; Adelium caraboides; Helæus Brownii, and piceus ; Eurhinus muricatus ; Curculio mirabilis ; Stenocorus punctatus ; Molorchus cingulatus ; Leptura ceramboides ; Chrysomela Curtisii ; Scutellera dux ; Achilus flammers ; Thynnus annulatus, and variabilis; Xylocopa Australensis; and Formica intrepida, and viridis.

Some Account of the Island of Tristan da Cunha, and of its Natural Productions. By Capt. Dugald Carmichael, F. L.S. Having permission to accompany the British troops who took possession of this solitary island, in November, 1816, Captain C. has communicated the results of his personal observations, in a very interesting manner. The whole island figures like a solid mass of rock, in the form of a truncated cone, about nine leagues in circumference, rising abruptly from the sea to the height of three thousand feet; and surmounted by a dome upwards of five thousand feet in height, terminating in the crater of an extinct volcano. Brush-wood, fern, and long grass veil the greatest portion of the mountain, from its bottom to the base of the dome: but its bare patches discover a numerous series of horizontal or slightly inclined strata of trap, between which are frequently interposed beds of scoriæ, tufa, and volcanic ashcs. Only a small portion of the plain promises to be susceptible of culture; and regular trenching, and the removal of loose stones, will be requisite to render the soil fit for the plough.

• The ascent to the peak is practicable in sundry places; but the undertaking is attended with serious difficulties, and not free from danger. I went up on the 4th of January, accompanied by Dr. Evers, a couple of servants, and a guide, who had been up some days before. We experienced some obstruction at the outset in making our way through the long grass ( Spartina arundiñacea) which grows along the lower part of the mountain in close entangled tufts. As we advanced, our progress was retarded by the extreme steepness of the ascent, and the loose incohesive nature of the rocks, which we could hardly venture to touch, lest these fragments should fall upon our heads; nor did we run less risk in availing ourselves of the branches of the arborescent Phyo lica to support our weight; for the greater proportion of these being rotten, it was necessary for us to choose with caution, as a mistake might prove fatal. After a laborious effort of three hours, however, we gained the table land, and there discovered to our mortification, that the upper région of the mountain was com

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pletely obscured. Urged by a strong west wind, the cloud broke from time to time against the sides of the dome, and gave us a transient glimpse of the peak at a height and distance that were by no means encouraging. After resting, however, for a few mi. putes, we proceeded across the base of the dome, trusting that the cloud would be dissipated by the meridian sun; nor were we in this respect altogether disappointed. In the mean time, we found the ground as we advanced a perfect swamp, studded with tufts of small rushy plants, that gave way under the slightest pressure. Here also we had to pass through extensive patches of fern (Lomaria robusta), the stems of which, like junks of old cable, trail along the ground, and cross and recross each other in such an in tricate manner, that it required all our circumspection to avoid stumbling over them. Further on, the ground becomes more firm, but is perforated in all directions by the various species of Petrel, which resort in myriads to the island during the season of incubation, and burrow in the earth. The weaker tribes of these birds are devoured in vast numbers by the Skua gulls, which pounce upon them as they come out of their holes in the evening, and leave nothing but the bones and feathers to attest the havock made among them.

« The surface of the dome is furrowed on every side with ra. vines, which take their rise among the scoria of the peak, deepen as they descend, and open in tremendous chasms on the edge of the precipice. The various portions of the surface thus cut off in a great measure from all mutual communication, grow narrower and narrower as you approach the base of the peak, and dwindle at last into bare ridges of scoria, so sharp and so steep, that the wild goats of the mountain dare hardly venture to thread them.

That ridge in particular over which we must either have passed or returned without accomplishing our object, is for at least fifty yards not more than twelve inches in diameter. The wind blowing in violent gusts at the time, rendered it the more difficult to maintain that strict equilibrium of body, the slightest bias from which, either to one side or the other, would precipitate any of us in an instant to the depth of several hundred feet. We got safely over it, however, though with some trepidation, and in a manner as various, I believe, as the number of our party would admit of.

• A short way beyond this ridge vegetation ceases ; not so much, however, owing to the elevation of the ground, as to the total want of any kind of soil wherein plants could fix their roots. From this point to the summit, a distance of about a mile and a half, the whole is a mass of scoria, fragments of cellular lava, and all sorts of volcanic refuse, constantly slipping under your feet, and rendering the toil of ascending excessive. For nearly a mile wo walked along a ridge of blue lava, which seems to have been at one time covered over, but afterwards left exposed by the gradual recession of the loose matters which covered it. In grain and colour it resembles the veins which intersect the isl mass; but is disposed on the slightest stroke to break into small amorphous fragments. S4

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• The crater is nearly a mile in circumference: its border is irregular, the south side being two or three hundred feet higher than the north, by which we ascended. At the bottom of it there is a pool of water about one hundred and fifty yards in diameter, to which the descent by the north side is gradual and easy. Its depth appears to be inconsiderable, as we could discover the bottom more than half way across; and its border is covered with rounded fragments of cellular lava, which float about at the hu. mour of the breeze. The water is pure, and untainted with any mineral solution. From the peak we could see the distant ocean on all sides over the cloud which still shrowded the lower part of the dome; but no part of the low land can be seen at any time, being covered by the projection of the table land. I found several mosses on the summit of the peak and some lichens, among others the L. paschalis. There was also a large patch of snow a considerable way down its side, and another within the crater.'

During their descent, the attention of the party was invited to the incubation of the Albatrosses, four species of which breed in the island:

· The black albatrosses (Diomedea fuliginosa) are at this season gregarious, building their nests close to each other. In the area of half

an acre I reckoned upwards of a hundred. They are constructed of mud, raised five or six inches, and slightly depressed at the top. At the time we passed, the young birds were more than half grown and covered with a whitish down. There was something extremely grotesque in the appearance of these birds standing on their respective hillocks motionless like so many statues, until we approached close to them, when they set up the strangest clattering with their beaks, and, if we touched them, squirted on us a deluge of fætid oily fluid from the stomach.

• The D. chlororynchos builds its solitary nest in some sheltered corner, selecting in particular the smal) drains that draw the water off the land into the ravines. There it runs up its nest to the height of ten or twelve inches, of a cylindrical form, with a small ditch round the base. A curious circumstance with regard to this bird is, that when irritated the feathers of its cheeks are separated, so as to display a beautiful stripe of naked orange skin, running from the corners of the mouth towards the back of the head.

All of these birds nourish their young by disgorging the contents of their stomach. They are never observed to carry any article of food in their bill: those matters, indeed, from which they derive the chief part of their sustenance, the blubber of dead whales, seals, and sea-lions, would melt away if carried in the bill to any distance. We could not help admiring the utter unconsciousness of danger displayed by them on our approach : they never showed the least disposition to move out of our way: even when kicked or pulled off their nests, they made not the smallest show of resistance; but quietly returned to their post, or stood still until we passed on. Their plumage is in the finest order, copious, and without the slightest stain. They find great difficulty in getting on wing, and must run twenty or thirty yards along the ground with expanded wings before they can get fairly under way. We had the curiosity to take one of them by the point of the wings and Aing it over the rock; yet, though it had several hun. dred feet of a clear fall, it never recovered itself, but dropped down like a stone. On this account, when not engaged with their young, they usually rest upon the edge of the precipice, from which they can launch at once into the air; and on entering again upon that difficult part of our route, we had to kick up.wards of a dozen of them to the right and left of us before we could get on. We arrived at the cantonment about sun-set, after a most fatiguing journey of fourteen hours.'

The climate of this island, notwithstanding its liability to frequent rains, is extremely mild and salubrious: but, owing to the spongy nature of the soil, and the many rifts and fissures in the rocks, it is very deficient in springs. Among the native animals, Captain Carmichael specifies Phoca leonina and Australis, various sorts of sea-fowl, including ApteRodytes chrysocoma, or crested Penguin, and four species of fish; which he particularly describes under the appellations of Chalodon monodactylus, Perca antarctica, Callionymus diacanthus, and Labrus ornatus. Only fifty-five species of plants are enumerated.

Some Account of the Spiral Tubes or Ligaments in the Genus Terebratula of Lamarck, as observed in several Species of Fossil Shells. By Mr. James Sowerby, F.L.S. — The precise purport of this short paper will be best understood by comparing the text with the plates.

On the Use of the Pedes Scansorii of Birds. By the Reverend Revett Sheppard, F.L.S. — The disposition of two toes before, and two behind, has been remarked only in a few genera of birds; and the present intelligent observer shews, satisfactorily, that it is not particularly available for climbing, although it is subservient to other purposes. The Cuckoo is not a climbing bird; and yet the conformation of its feet is the same with that of the Wood-peckers; whereas the Nut-hatch and Tree-creeper, which run up and down trees, have their toes placed in the usual manner. The two hindtoes of the Cuckoo enable it to preserve its balance when it bends forwards, the attitude in which it pours forth its pleasing and protracted note. By the same adaptation, the Parrots more securely grasp their food, step from one branch to another, or remain in a suspended position. With respect to the Wood-pecker, the author observes that, in boring trees, (in which occupation the bird is often engaged for a considerable length of time,) its weight is thrown backward, and thus

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