mistakes would they not have anticipated! and yet, perhaps, the pleasure of working one's own way, and gleaning information painfully and almost in the dark, afforded more real enjoyment than even to get information thus ready prepared and perfected. The whole district of Edinburghshire is exclusively a coal-field, forming a portion of that great Palæozoic deposit which occupies the basins of the Firths of Forth and Clyde, extending from sea to sea on the east and west. A sketch of the filling up of this great basin or open sea, from the commencement of the Carboniferous era to its close, and the elevation of the whole by the intrusion of trap-rocks, was then given,-the total absence of all appearances of subsequent formations, from the Coal to the Tertiaries inclusive, in this district,-then the numerous traces of the glacial operations visible in the drift,—the evidences of a greater extension of the present estuary of the Forth at the close of this glacial period, and the movements and changes of level, which probably had a considerable effect in moulding the present aspect of the district posterior to the glacial deposits. The earliest notices of the working of coal in this district, and probably in Britain, occur in charters obtained by the monks of Newbattle to dig coals on the Pinkie Burn, near Tranent, in the years 1200 and 1284. But it was several centuries after this before coal came into general use. We read of frequent fires occurring in Edinburgh from the ignition of stacks of heather, furze, and peat, which it was the practice of the citizens to collect and carefully pile up in the areas and closes for fuel. And so late as the year 1560, robberies were so common on the streets in the dark winter nights, that a rope was tied across the principal thoroughfares, to which a bowat or lantern was suspended in the centre, containing a single tallow candle, which "paled its ineffectual fire," where now, in the same localities, gas blazes, and innumerable coal fires enliven the gloom of the winter nights. It is well known that Newcastle coal was prohibited to be used within the city of London by act of Parliament, on account of its "noxious, sulphureous, and pestilent smoke;" while at the present day no less than seventy millions of tons of coals are raised

in Britain. A small portion of this is exported, but the great bulk is used for domestic purposes and manufactures, -for animating the giant arm of the steam-engine, and for sending our steam-ships over every region of the globe. The present aspect of the county was next alluded to,-its division into three alluvial valleys, watered by three rivers which flow into the estuary of the Firth,-the Pentland range of hills, their diversified scenery, and the remarkable basaltic rocks surrounding and forming the basis on which the city is built. There are no means of knowing what was the condition of the local atmosphere of Mid-Lothian in former times-at periods when the country was more densely covered with wood, when the ancient forests of Scotland still remained, when the surface of the soil was only partially cleared and cultivated, and imperfectly drained, and when marshes and lochs were greatly more abundant than they are at present. In the absence of actual facts, people are apt to draw on their imaginations and feelings; and it depends a good deal on the individual temperament whether we hear that the seasons are become much more severe and ungenial, or warmer and drier, than they were in bygone days. It was only towards the end of last century that scientific instruments were employed to indicate the climate of the country. From those begun by Professor Playfair in 1771, and others, continued down to the present day, it appears pretty evident that no change of climate has taken place during the last ninety years. Considerable varieties of seasons occur; the general or normal was pointed out, and the occasional or abnormal, with their distinctive peculiarities, and the great leading or general causes of difference, traced to the predominating power of the southwest and north-east air currents,-the predominance of one or the other forming the main cause of the varieties of seasons, and to the influence of the great Gulf Stream, which flows past the British Isles. Local ameliorations of climate by drainage, cultivation of the soil, protection of plantings, &c., while they are of the greatest importance to the agriculturist and in a sanitary point of view, would appear to be too small to affect the general climatal averages. The

mean annual temperature of the lower portion of the county, embracing a series of years, may be stated at 47-2 Falır.; the rain-fall 24-6 inches. The mean annual temperature of the city of Edinburgh, for the last three years previous to 1860, is 48°3 Fahr., by the lists of the Meteorological Society. This is equal to if not higher than the annual temperature of any of the Scottish towns, and only 2° lower than London. The annual rain-fall at Greenock, on the west coast, is two-thirds more than that of Mid-Lothian. Mr Rhind concluded by recommending to the members of the Society, of whom there were several eminent in the various departments of natural history, to combine their labours in a complete investigation of the physical history of the county. We owe much, he said, to the labours of our predecessors in this respect; and it is but just that we should endeavour to do something for those who are to succeed us.

A vote of thanks was unanimously given to Mr Rhind for his address, and his valuable services while President of the Society, his term of service having now drawn to a close.

The Secretary was instructed to engross in the minutes of the meeting portions of the President's address referring to the death of Mr William Oliphant; and to send an extract of the minute to his widow, Mrs Oliphant, as a mark of the Society's respect for the memory of its late member and office-bearer, and of sympathy with her in her bereavement. The following communications were then read:

I. Observations on British Zoophytes and Protozoa.

(1.) Notice of Ophryodendron abietina (Corethria sertularia). (2.) On the Reproductive System of Chrysaora. By T. STRETNILL WRIGHT, M.D.

(1.) On Ophryodendron abietina.—Amongst the lower classes of animals, and especially in the Protozoa, the lowest class, numerous and very striking examples of homomorphism occur. "Homomorphism" is an exact similarity in form between animals of different classes, without any corresponding resemblance in their anatomical strucSome of these examples may be considered fanciful, as the likeness between Lacrymaria olor and the fossil

ture.

reptile Plesiosaurus. But in others the homomorphism is so perfect, that animals belonging to the lower class were long confounded by the most eminent zoologists with those of a higher class. Thus, various species of the Foramenifera were classed amongst the Cephalopoda. The shells of many of the Foramenifera are, indeed, exact copies of those of Cephalopoda, both recent and fossil. The recent Nautilus and Argonaut, and the fossil Baculite, Orthoceratite, Hamite, and Ammonite, find their representatives in the microscopic Numulina, Polystomella, Dentalia, Cristellaria, and Rotalina. The shells of the former are inhabited by the highly organised cuttle-fishes; those of the latter by creatures which can scarcely be said to possess any organization. The chambers of their shells are filled with a glairy living mass, which streams like a fluid in and out through the innumerable minute pores with which the shells are pierced. The streams unite together to form widely-spread meshes and expansions, which envelope, absorb, and digest smaller living beings coming in contact with them, and on which the animals move, or rather flow along. But although the forameniferous animal is a mere fluid mass, destitute not only of organs and stomach, but even of the simplest cellular structure, it is yet capable of exercising the most important functions of life-motion, nutrition, and reproduction, and of erecting for itself edifices mathematically correct in design, which arrest the eye by their exceeding beauty of form and ornamentation, and which, deserted by their tenants through successive ages, have formed no inconsiderable part of the solid frame-work of our globe. A curious instance of "homomorphism" occurs in the subject of the present notice, Ophryodendron abietina, which is fashioned after the type of Sipunculus Bernhardi, a highly organised Echinoderm. This animal consists of a shapeless oblong mass, immoveably fixed to the corallum of Sertularia pumila. From one end of the mass arises a closely wrinkled proboscis, surmounted by a tuft of short tentacles. The proboscis can be entirely withdrawn into the body, or extended to an astonishing length, until it appears as a clear glassy wand,

twenty times as long as the animal, and clothed at its upper part by about forty scattered tentacles, which twine about in most violent motion. The animal seems to be constantly searching the water around for prey, and occasionally to press the tentacles firmly against the body of the proboscis, as if to imbed some matter into the soft substance of the latter the usual mode of feeding amongst the Acinetiens, to which class it belongs. It is impossible not to be struck by the extreme similarity in outward form between this animal and the Echinoderm Sipunculus Bernhardi. In both animals occur the same shapeless body, the same entirely retractile proboscis crowned with tentacles, and the same peculiar motions in seeking for prey. But with the form, the similarity ends, for the Echinoderm possesses a highly organised structure, while in the transparent Protozoon no structure at all has been detected.

(2.) On Hermaphrodite Reproduction in Chrysaora hyoscella. (Plate IX).-Professor Allen Thomson, in his "Treatise on the Ovum,"* states that "the Discophora (Medusa) are of distinct sexes." I have found this to be the case in all the Steganophthalmata and Gymnophthalmata which I have examined, with the exception of the subject of this notice.

Large individuals of C. hyoscella are hermaphrodite; but smaller ones are found which are unisexual, the male or female element being suppressed, as in some diœcious plants.

The best method of examining the structure of the reproductive apparatus of this animal is to place the Medusa, in its natural position, in a large basin of sea-water. The umbrella, all but its margin, is then to be cut away. The cavity of the stomach is thus laid open, and we have a good view of the interior aspect of the sub-umbrella. We find that each lip of the mouth divides, at its insertion, into three pillars. The central pillar projects as a large rounded bulb into the stomach, while the lateral ones diverge, pass outwards towards the margin, and afterwards converge and unite together, so as to form, with the bulb of the central pillar, the thickened opening or framework of the ovarian

* Cyclopædia of Anatomy and Physiology, vol. v. p. 129, "Acalephæ,"