A discussion took place on various results of recent explorations, when some interesting statements were made by several members on points bearing on natural history which had been established by the Arctic and Antarctic expeditions. Mr Harvie-Brown mentioned that the nesting-place of the Knot-Tringa canutus—had now been discovered, and although its latitudinal range is restricted, its longitudinal range may be widely extended. The Knot is perhaps more generally distributed than any other species, but hitherto its breeding haunts could not be fixed with any certainty. He also stated in evidence of the rise of the land in the Arctic zone, at a comparatively recent date, that in Northern Russia-the shores of the Petchora Gulf being thickly strewn with piles of drift wood carried down by the great rivers-he had observed that where the tundras approached the margin of the Arctic sea, and formed banks of a considerable height, they were strewn for some distance inland with drift wood, which must have lain there for a very long period, and which must have been deposited when the tundras were almost on a level with the water.

SPECIAL

MEETING.

NATURAL HISTORY CLASS ROOM, GLASGOW UNIVERSITY.

DECEMBER 21ST, 1876.

Professor John Young, M.D., F.G.S., F.R.S.E., President, in the chair.

ADDRESS BY THE PRESIDENT.

Professor Young proceeded to discuss the geological bearings of some of the results arrived at by the Challenger and other exploratory expeditions. He showed an enlargement of the map prepared by Mr John Murray of the Challenger staff, and on it pointed out the distribution of the various deposits referred to in Mr Murray's paper, read in section D of the Glasgow meeting of the British Association. The red clay suggested reference to Professor Ramsay's theory as to the origin of the red rocks in the stratigraphical series. Professor Ramsay founded on the improbability of peroxide of iron tinging deposits in the open sea, whereas peroxide of iron and manganese were found to be the

colouring nucleus of the red clays. But while this part of the theory did not admit of general application, the conclusions arrived at regarding the conditions under which the old red sandstone and permo-triasic strata were laid down remained untouched, since these latter were sandy deposits, shale being very subordinate.

The occurrence of a non-calcareous accumulation in the deepest waters was next discussed, as bearing on Professor Hull's views regarding calcareous rocks. After stating the still debated issue as to the decalcification of the Globigerina ooze and the conversion of the non-calcareous part into red ooze, Dr Young suggested that perhaps we have not yet recognised the deepest water accumulations, which, if the events of the remote past are identical with those of the present, must have corresponded to the mountain limestone or the chalk. Again, the area over which the calcareous material might be spread was shown by the distribution of the coral mud at the present to be far greater than that occupied by the animals whose skeletons went to make up the deposit. Moreover, oscillations of the ocean floor might bring into seeming succession to each other accumulations which were in reality contemporaneous, and Dr Young dwelt on this as helping to bear out the suggestions contained in his British Association address, to the extent, that the thickness of the stratified deposits, and, as a consequence, the time required for their deposition, might be over-rated. The uniformity of aspect presented by the deep sea fauna has an important bearing on the views of Salter and others, who regard the wide distribution of mountain limestone fossils as evidence of the greater uniformity and consequently smaller number of types of animals in the earlier period. If we have to do with the inhabitants of deep waters in these limestone fossils, there might have been, and probably was, at these early times, as great a diversity as now.

After glancing at the controversy regarding ocean circulation, and pointing out wherein the data were as yet incomplete, on which a satisfactory judgment could be based, Dr Young referred to the question of the possible increased salinity of the existing seas, and asked if Mr Buchanan's results, when fully wrought out, might not support, by the constancy of high specific gravity below certain depths, the notion that the ocean might be, as has been suspected on theoretical ground, salter than it once was; in fact, that

the ocean might prove to be on a large scale what the Dead Sea was on a small one. Dr Young next referred to the occurrence of coal of cretaceous age in the far north, and the bearing of this fact on the possible change of the earth's axis of rotation. He spoke of Nordenskiold's and Judd's objections to the current doctrine of a glacial epoch and polar ice-caps, and of Professor Ramsay's caution against exaggerating the importance of glacial deposits and treating them as of equal value with the Silurian or Carboniferous strata; lastly, he referred to the distribution of the manganiferous deposits as shown by Mr Murray, but left it to Mr Young to discuss this point in reference to the limestone at Cunningham Bedland, which Mr Young had got analyzed.

SPECIMENS EXHIBITED.

Dr Young exhibited the type specimens of Ellis and Solander's corals, which, to the number of nineteen, he had identified in the Hunterian Museum; also a case of Bohemian trilobites received from Dr A. Fritsch.

Mr John Young, F.G.S., exhibited specimens of a small reticulated sponge found by Mr James Armstrong, of the Glasgow Geological Society, in the same deposit of rotted Carboniferous limestone at Cunningham Bedland, near Dalry, in which the sponge spicules, Acanthospongia Smithii, exhibited at a former meeting, were obtained. Mr Young stated that it was of interest to know that, besides the occurrence of siliceous sponges in this deposit, there was the evidence of the presence of sponges belonging to other groups in the same family. Mr Young also exhibited a sample of the peculiar reddish-brown mud in which the sponges and other organisms are found. This mud is the inorganic residue of the limestone left in the eroded fissures of the rock through the action of water charged with carbonic acid. From its resemblance in colour to the manganiferous mud found by the Challenger expedition over certain of the deeper parts of the sea bottom, it had occurred to Mr Young that this residue of the rotted limestone might also contain manganese, and he therefore had a small quantity tested at the laboratory of Glasgow University, when it was found that the mud, when fused with carbonate of soda, gave a decided greenish tinge, forming a manganite of soda. No quantitive analysis of the amount of manganese in the mud had been made, but it was thought that there could not be less than

2 to 3 per cent. present. Mr Young stated that it would be interesting to determine whether the manganese had entered into organic combination with any of the numerous organisms found in this bed of limestone, or had been chemically precipitated as a deposit from the sea water. From what he had read of the manganiferous mud found by the Challenger, he was inclined to hold to the opinion already expressed, that it was the result of decalcification of the Globigerina ooze, the manganese having been extracted from the sea water and entering into the composition of the animal shell structure of these minute organisms. He therefore did not agree with the other expressed view that it had been floated to these deep tracts of the sea bottom in company with other inorganic elements. If the former view should prove to be the correct one, we might naturally expect that manganese would be present to a small extent in many of the limestones of organic origin in all the formations. In the Carboniferous limestones of the West of Scotland he knew of limestones that yielded a reddish mud on erosion by carbonic acid. It would therefore be interesting, as bearing on the red mud found by the Challenger, to prove to what extent they also are manganiferous.

ANDERSON'S UNIVERSITY BUILDINGS.

JANUARY 9TH, 1877.

Mr James Ramsay, V.P., in the chair.

Messrs. Alexander B. Stewart and Charles Malloch were elected life members; and the Rev. H. B. Tristram, LL.D., F.R.S., C.M.Z.S., Canon of Durham; Messrs. Andrew Malloch Bayne, Peter Marshall, A. D. Newlands, James Lyle, Robert Marshall, and Thomas Scott Forrest, ordinary members.

SPECIMENS EXHIBITED.

Mr John A. Harvie-Brown, F.Z.S., exhibited a rare Little Rail, Ortygometra affinis, Grey, from New Zealand, and remarked that Buller ("Birds of New Zealand," page 183) describes, but does not figure this bird. He tells us that it "closely resembles the Australian O. palustris, but is distinguishable by its somewhat larger size, and the absence of white markings on the primaries."

He tells us, also, that "This handsome little crake is found in both islands; but it is everywhere extremely rare and difficult to obtain. It frequents the sedgy banks of creeks and rivers, and the reed-covered lagoons near the coast.

is at present known of its breeding habits."

Very little

This specimen was shot by Mr J. R. Cook, in Canterbury province, New Zealand. Mr Cook stated that it was the only one he had shot during a residence in New Zealand of twelve years. As this bird is so rare, Mr Harvie-Brown said that he thought it well to give a description of this specimen, which is appended.

Ortygometza affinis, Grey. "Voyage of the Erebus and Terror," 14. Buller, page 183.

Measurements-Bill at front, 1 inch; middle toe and claw, 13 inches; wing, from carpal joint, 3 inches; length 6 inches. Buller gives as total length, 7.5 inches. The difference may result from the specimen described by him having been measured in the flesh.

Description-Bill bluish-black, faded apparently from dark green or olive. Crown, and neck above, dark yellowish-brown, with blackish centres to the feathers. Back, scapulars and wing coverts, yellowish-brown, tinged with faint olive, many feathers being laterally marked with blackish, and some having one or two irregular white spots on the outer webs. Cheeks, and breast down the centre and under parts, bluish-grey. Throat greyishwhite. The yellowish-brown of the upper parts extends down the sides of the breast and flanks. Sides of the abdomen blackishbrown, broadly but irregularly barred with white, as are also the under tail coverts. Tail feathers same as longer bastard wing feathers, but without the white spots. Primaries smoky brown.

Mr James Lumsden, F.Z.S., exhibited a specimen of a hybrid between the Black Grouse, Tetrao tetrix, and the Capercailie, Tetrao urogallus, and on the table had placed examples in illustration of these two species. He said that at the November meeting of the Society in 1872, he had the pleasure of exhibiting a very fine female of this kind. The one he now showed was a male, and he had little to add to the remarks which were made on the occasion referred to. These hybrids have been long known in Sweden, but some years ago Russian and German naturalists, thinking they had made a discovery, elevated the bird into a