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top of the Devonian system. The Boulogne beds chiefly belong to this series, as does the "Spirifer-Verneuili-schiefer" of the Prussian geologists.

It is overlain, along the course of the Barnstaple River, by the representative of the Carboniferous slate, and this again by the Mountain-limestone series in a greatly altered form.

The Marwood and Pilton group, at least in part, can be thus proved by fossils to be the actual equivalent of the Upper Old Red Sandstone, a formation which has been found in some parts of the British Isles to be unconformable on the Lower Old Red Sandstone.

The identification of this Old Red Sandstone with the Devonian beds has been a point hitherto singularly destitute of proof, though its suggestion by Lonsdale, and subsequently by Austen, Sedgwick, and Murchison, in memoirs on Devonshire and on the Rhine, has been generally approved.

So little proof existed of this identity, that one of our best observers, whose research had largely tended to the establishment of the Devonian series (Mr. GodwinAusten), has recorded his doubts in the Geological Society's Journal (vol. ix. p. 231), identifying the Old Red Sandstone only with the uppermost or Marwood beds, which Mr. D. Sharpe considered as Carboniferous; while Mr. Sharpe himself placed the Old Red Sandstone at the base of the Devonian system (vol. ix. p. 20, &c.).

The fossil clue has once more unravelled a geological difficulty. Sir R. I. Murchison, in reclassifying the beds of the Old Red Sandstone of Scotland (Siluria, 2nd edit. p. 285), has shown good reason for considering the order of superposition to be as follows:-from the base,

1. Lower Old Red, with Cephalaspis, Pteraspis, Pterygotus.

2. Middle Old Red, with Coccosteus, Diplopterus, Osteolepis, Pterichthys, &c. 3. Upper Old Red, with Holoptychius, Glyptopomus, &c.

The Upper Old Red, then, being identical with the uppermost Devonian, it remains to be seen if we can find fossil links between the middle and lower members of each respectively.

It has been repeatedly shown that Coccosteus, a fish characteristic of the middle Old Red beds, occurs in the Eifel and the Harz, in strata which belong to the Middle Devonian; and in Russia* it is common to have this and other genera (Asterolepis, Dendrodus, &c.) in beds of sandstone intercalated with the marine shells.

There is still the Lowest Devonian zone, viz. the Spirifer-sandstone of the Rhine. The lower sandstones and slates of Linton, in N. Devon, and of Fowey and Torquay, in S. Devon, are its equivalents. In order to prove this zone identical with the lowest Old Red-the Cornstone group, it was needful to find some at least of the characteristic fish in it. In no Old Red locality have we any marine fossils mixed with the Cephalaspis and Pteraspis; but in one of the German localities Prof. Roemer has lately discovered, and Prof. Huxley described (Quart. Journ. Geol. Soc. 1861), a large species of Pteraspis-a fish so exclusively characteristic of the lowest Old Red as to leave no doubt whatever of the true correlation of the two deposits.

Upper, Middle, and Lower Old Red are, therefore, now linked in all their parts by fossils with Upper, Middle, and Lower Devonian.

On a Skull of the Rhinoceros tichorhinus.

By S. P. SAVILLE.

On a Whittled Bone from the Barnwell Gravel. By H. SEELEY, F.G.S. This was the proximal end of a dorsal rib of a large mammal, seemingly the Elephant, obtained by the Rev. F. J. Blake from the gravel-pit at Barnwell, near Cambridge. The specimen shows on the severed end numerous cuts, as though made to assist in breaking the bone. The author urged that, as the condition of the cut surfaces was like the external surfaces-as they had passed unnoticed till he detected them-as similar cuts could not be made on fossil bones without great care and chemical preparation, and there was nothing to suggest a doubt as to their * Siluria, 2nd edit. p. 382, 421, &c.; see also vol. xv. p. 437.

authenticity, the cuts were as old as the date of fossilization. And as bones are there only found in one band of loam, it was further urged that they might be taken as evidence of the coexistence of man in that district with the Irish Elk, Bos primigenius, Elephas primigenius, Hippopotamus major, and the other mammals of the gravel.

On a Successful Search for Flint Implements in a Cave called "The Oyle," near Tenby, South Wales. By the Rev. GILBERT N. SMITH,

This is a cave in the mountain limestone, about 70 feet above the level of the valley beneath, up which the tide has till very recently been used to flow,

Within, it is distinguished by chambers, alternating with narrow passages, penetrating 30 or 40 yards into the spur of a ridgeway of the Old Red.

Floor not more than 3 feet deep anywhere, and bearing traces at the sides of a stalagmite covering long since destroyed.

Seventy-three artificial flakes or chips were unearthed, together with the identical lumps of flint which remained after the chips were struck off, when, from their reduced size, they were no longer capable of yielding flakes sufficiently large to answer the destined purpose.

Some of the chips are of ordinary flint; some of a dull green, opake chert. In size they vary from about 4 inches in length to half an inch. In general form they are almost identical with the flakes found at Red Hill. They were disseminated through the soil of the whole cave, but much the most thickly scattered on the floor of a recess near the entrance.

Interspersed also with them through the soil, which in some places is nearly black, were a great many bones. Most of these belong to such ruminants as are now domesticated. Some are of the usual cave-mammals, as Ursus spelaus, &c. One very fine front prong of an antler lay by itself in black earth, and has marks as of a tool. Length 11 inches; circumference at base 4 inches.

The lowest portion of the soil seemed quite undisturbed, down to the rock. It is similar to the drift around the cave. Plenty of edible-mollusk shells occurred intermixed.

The investigator believes these flints to belong to the same human family that raised seven or eight tumuli which exist above on the ridgeway, which contained flint arrow-heads and a central kist vaen, or covered cromlech.

He is of opinion that these flakes are the neglected refuse of the workshop, there being no perfected flint arrow-heads among them, like those in the barrows, though there are eight broken pieces of perfected ones among the seventy-three specimens.

The Welsh antiquaries here do not find mention of any weapons of stone among their ancient writings, except for sacrificial purposes,-in accordance, this, with Joshua v. 2, where flint knives are prescribed to circumcise, which Lightfoot says was a kind of sacrifice also. The most eminent Welsh scholars have been consulted by the writer.

There is no flint in the strata of this neighbourhood; and the chert, which has small white spots through it, and looks more like some fine kinds of trap, does not appear in the coast-strata, although sea-borne boulders of granite and an occasional flint may be picked up, with here and there a worn fragment of serpentine and iridescent plutonic rock.

On the Cause of the Difference in the State of Preservation of different kinds of Fossil Shells. By H. C. SORBY, F.R.S., &c.

The fact of certain kinds of fossil shells having lost their organic structure, or being entirely removed, whilst in the same bed other kinds remain almost in their original state, cannot fail to have attracted the attention of most geologists. For example, most univalve and such bivalve shells as Trigonia, and the inner layer of Avicule and Spondyli, are often altered or removed, though their outer layer and the entire shells of Ostree and Brachiopoda are well preserved. After having made a considerable number of experiments with recent and fossil specimens, the author had come to the conclusion that this difference was due to the original

difference in the state of the carbonate of lime; and that, other conditions being the same, shells which were composed of calcite are preserved, whereas those composed of arragonite have been altered. This appears to depend on the fact of the particles of arragonite being in a state of unstable equilibrium. When prepared artificially, it has a great tendency to pass into calcite; and if this change took place in shells, their organic structure would be very apt to be destroyed, though the shell might remain as a crystalline mass of calcite. If, however, the circumstances of the case were such that the calcite formed at the expense of the arragonite of the shells had a greater tendency to crystallize elsewhere rather than in situ, they would be removed, and leave more or less perfect casts. On the contrary, calcite having no such tendency to change, shells composed of it might, under similar conditions, remain nearly in their original state.

On the Comparative Structure of Artificial and Natural Igneous Rocks. By H. C. SORBY, F.R.S., &c.

As is well known, Sir James Hall and Gregory Watt, by fusing and slowly cooling basalt, obtained a stony mass, to a certain extent similar to the original rock. Various writers on the subject have since contended that the product is not, like the original, composed of several distinct minerals, but made up of only one kind of crystals. The author, however, showed that, when thin transparent sections are examined with a high magnifying power, it may be seen that the artificial rock is really an aggregate of the three principal minerals of the original basalt, which, nevertheless, are developed and arranged in such a very different manner that it is easy to understand why this fact has been overlooked. Indeed, the difference in general structure is so considerable that, probably, other causes besides a slower cooling were instrumental in producing the peculiar characters of the natural rocks.

On Scutes of the Labyrinthodon, from the Keuper Bone-Breccia of Pendock, Worcestershire. By the Rev. W. S. SYMONDS, M.A., F.G.S.

The remains of this Triassic reptile have been found in the Keuper sandstone of Warwick and Leamington, but had not hitherto been detected in the Trias of Worcestershire or Gloucestershire. The scutes and bones found by Mr. Symonds were submitted to Prof. Huxley. They occur chiefly in the "bone-breccia," described by Mr. Symonds in the 'Transactions of the Geological Society,' and are associated with numerous spines of fishes.

On the Geology of a Part of Sligo. By A. B. WYNNE, F.G.S.

In this paper the author stated that he had put together a few notes upon an extensive district. They were made during a short tour to the co. Sligo and part of Leitrim, in the summer of 1862; and he alluded to papers by Sir R. Griffith, Archdeacon Verschoyle, and Mr. John Kelly, in the 'Proceedings of the Geological Society,' all of which referred to the country under consideration. He then proceeded to describe the district as composed of a widely spread, nearly horizontal series of stratified rocks, consisting of sandstones below and above, with a thick band of limestones interstratified with other sandstones between. This horizontal group represents the Carboniferous formation, from the Millstone-grit downwards, and probably a part of the underlying Old Red Sandstone; and the thickness of the group is little less than 2000 feet, roughly estimated from the heights of the mountains formed by these rocks. Cutting across the country formed by these horizontal beds is the rugged chain of the Ox Mountains, extending from Mayo into the co. Leitrim. Some of the most picturesque valleys in the district, like that of Lough Gill, are the lateral ones along the flanks of the Ox chain, which, being formed of gneissose, micaceous, and quartzose rocks, have a totally different aspect from the mountains formed of the limestone and other horizontal beds. The serpentine garnet rock and trap-rocks of these older mountains were next alluded to, and it was stated that, although they seemed to occupy fissures running in various opposite directions, their master-joints or divisional planes were nearly parallel. The denudation which exposed the Ox Mountains, and removed the thick series of

Carboniferous rocks which curves round the eastern end of the chain, was alluded to; and the circumstance of the occurrence of beds of sandstone interstratified in the limestone portion of the horizontal group was given as an instance of the splitting up of the Carboniferous formation into alternations of numerous arenaceous and calcareous strata, as observed in the northern parts of the British Isles. limestone was stated to be traversed by greenstone trap-dykes, and metalliferous mineral deposits were stated to occur at Lurganboy, King's Mountain, &c.

The

In conclusion, the drift was alluded to, and sea-shells were stated to have been found therein, in one place at a considerable depth, and at a distance of two miles from the sea; and the horns and skulls, &c., of deer and other extinct animals were mentioned as overlying this deposit, or being just within it. The paper was illustrated by drawings of different portions of the country, and a list of the fossils sent for determination to W. H. Baily, F.G.S., was appended.

ZOOLOGY AND BOTANY, INCLUDING PHYSIOLOGY.

BOTANY.

On the Ennobling of Roots, with particular reference to the Parsnip.
By JAMES BUCKMAN, F.L.S., F.G.S., &c.

The author, in this paper, explained the processes which he had adopted to convert the woody-branched root of the wild parsnip into the smooth, succulent, fusiform root of the esculent parsnip.

The growth of wild seed was commenced in 1847, in prepared garden-ground, and roots carefully selected and transplanted for the next generation, and so on, selecting roots for seeding until the desired form was attained. This new variety of parsnip is now well known to the gardener under the name of the Student Parsnip The author concludes that his experiments with parsnips sufficiently show that this esculent, as well as the carrot, beet, turnip, &c., have nowhere in the wild state that large, fleshy, smooth appearance which belongs to their cultivated forms; and hence, that all the varieties of these that we meet with in cultivation must be considered as derivatives from original wild forms, attained by cultivative processes.

He states that the facility with which new sorts can be induced, and the constancy with which they are maintained, under great diversities of soil, climate, and treatment, are evidences of the derivative or ennobled nature of our crop plants, which are indeed maintained by the very changes to which their aboriginals have been subjected.

Experiments with Seed of Malformed Roots.
By JAMES BUCKMAN, F.L.S., F.G.S., &c.

In this paper it was shown, as the result of direct experiment, that seed derived from malformed, i. e. misshapen, crop-roots of both turnips and parsnips resulted in even greater deformities than those presented by the parent.

Thus, a much-forked root of parsnip and another of a swede were selected for seeding, the produce of each being sown in plots side by side with that of good roots, the result of which was that in both instances the bad seed produced only about half the weight of the good, and all the examples of roots from the bad seed were misshapen in a most extraordinary manner.

From these experiments the author draws the following conclusions:

1. That a degenerate progeny will, as a rule, result from the employment of degenerate or badly-grown seed.

2. That, besides ugly, malformed roots, degenerate seed does not produce nearly the weight of crop of good seed under the same circumstances of growth.

*It gained the first prize at the International Show at the Horticultural Society for 1862. 1862.

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3. That, by means of selection, we may produce roots that are well shaped and have the capabilities of yielding the best crop.

4. That, by designedly selecting malformed or degenerate roots for seeding, we may produce a seed that will result in a great or greater degeneracy.

The bearings of this subject are of interest, not only in a physiological point of view, but in the more practical one concerned in every-day cultivation; for upon a due observance of the principles involved will depend the stability or permanency of any particular sort; and as sorts are only arrived at as the result of great care (that is, by successful breeding), so care must be taken for their maintenance.

Reply to the Remarks of M. F. Marcet on the Power of Selection ascribed to the Roots of Plants. By Dr. DAUBENY, F.R.S.

Dr. Daubeny replied to some remarks by M. F. Marcet, published in the Bibliothèque Universelle de Genève,' with respect to the power of selection exerted by the roots of plants, as mentioned in a paper read by him before the British Association at the last Meeting held at Manchester.-See vol. xxx. p. 141.

On a Botanical Chart of the Barony of Burren, County Clare.
By F. J. FOOT.

This district is composed of the Upper Carboniferous Limestone, and is remarkable as being the habitat of many rare and interesting plants. Certain lines were laid down on the map, representing the limit of the ranges of these plants through the district. Among others, the author enumerated and commented briefly on the following:-Arabis hirsuta, Arenaria verna, Cerastium arvense, Geranium sanguineum, Rubus saxatilis, Rubia peregrina, Galium pusillum, Galium boreale, Asperula cynanchica, Melampyrum sylvaticum, Orchis pyramidalis, var. fore pleno, Thalictrum majus and minus, Helianthemum canum, Spiræa filipendula, Dryas octopetala, Sedum rhodiola, Arbutus uva-ursi, Pyrola media, Gentiana verna, Orobanche rubra, Epipactis ovalis (of Babington), Potentilla fruticosa, Adiantum capillus Veneris.

The last-mentioned plant (the beautiful Maiden-hair Fern) occurs in great abundance in several separate stations in Burren. A few years ago it was only recorded as plentiful from the South Isles of Arran, and sparingly from Connemara and Cahirconree Mountain, county Kerry.

On the Inflorescence of Plants. By JOHN GIBBS.

On the Toot-poison of New Zealand. By W. LAUDER LINDSAY, M.D. and F.R.S. Edinb., F.L.S., &c.

During a tour through the New Zealand provinces in 1861-1862, the author was struck with the abundant evidences which everywhere presented themselves of the ravages produced among the flocks and herds of the settlers by the Tootplant, one of the most common indigenous shrubs of these islands. In many cases of losses by individual settlers brought under his notice, the amount from this source alone had been from 25 to 75 per cent. In Otago particularly were such losses felt during the height of the gold mania there, from July to December 1861: the traffic between Dunedin and Tuapeka gold-fields required the service of large numbers of bullocks, a great proportion of which were lost by Toot-poisoning. In colonies which as yet, at least, have depended for their prosperity almost solely on pastoral enterprise, such losses form a material barrier to prosperity; and the concurrent testimony of the colonists in every part of New Zealand proves the great desirability of determining the nature of the Toot-poison, the laws of its action on man and the lower animals, and its appropriate antidotes or modes of treatment. With a view to assist in the attainment of these aims, the author had made notes, on the spot, of a large number of instances of the poisonous or fatal action of the plant on man-adults as well as children--and the lower animals, and had brought specimens home for chemical examination. The chief results of his investigations may be thus stated :—

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