a purple tint, and the latter rests conformably upon shale which equally conforms to the seam of coal seen at Cullercoats and known as the Hebburn seam. In the red sandstones immediately above, and conformable to the Hebburn coal, Plants occur, consisting of species common in the Coal-measures. They have no relation to the true Permian Plants such as are obtained from the marl-slate of Durham and its equivalent-the Hilton leaf-beds of Westmoreland; and the evidence, both as regards stratigraphical arrangement and fossils, removes the sandstones north of Tynemouth from the Lower Permian or yellow sandstones of the Wear, and places them in the Carboniferous formation.

With regard to the nature of the Plants of the true Permian strata, they have a widely different facies from that which the carboniferous Plants present. No traces of either Lepidodendron or Sigillaria-so abundant in the Coal-measures-have been hitherto met with in the Permian rocks; and with reference to seeds, while Trigonocarpon, a fruit appertaining to the berry-bearing Coniferæ, occurs in the Coalmeasures, it is absent from the Permian group, the seeds occurring in the latter being the products of cone-bearing pines which make their appearance for the first time in the Permian formation.

Of these Coniferæ of the Permian strata, two forms of Ullmania, a genus unknown in the Carboniferous formation, are abundant, the cones of which seem to have been of small size; and as regards Ferns, these also in the Permian rocks are altogether distinct from such as occur in the Carboniferous group. The fossil plants are, therefore, characteristic of, and peculiar to, the Permian series; they also indicate different climatal conditions; and, if we may judge from the relative size of the cones of the Gymnosperms, we should infer that a somewhat lower temperature obtained during the Permian than during the Carboniferous epoch.

Although there is no great band of Magnesian Limestone like that of Durham and Yorkshire to mark the central division of the Permian rocks of the north-west of England, we hold that the series we have described in the Valley of the Eden is much fuller and thicker than its equivalent in the north-eastern counties. In the north-east of England, not only is the Lower Permian or Rothliegende most slenderly and imperfectly represented, but the highest member of the group is entirely wanting. On the other hand, the splendid development of the Magnesian Limestone, in its range from the coast of Durham through Yorkshire and into Nottinghamshire, is so much superior in volume to its feeble equivalent in the region under consideration, that some geologists may be induced to view the Upper Sandstones of St. Bees and Corby as synchronous with the Upper Magnesian Limestones and red marls of the Yorkshire series. In contrasting the siliceous character of the Permian group of the north-west of England with its eminently calcareous development in Durham and Yorkshire, it is to be borne in mind that even the latter band, when it trends southwards into Nottinghamshire, becomes so sandy a rock, that the freestones of Mansfield, of both red and whitish colours, might, from their aspect, be mistaken for sandstones. It was the least calcareous

of these masses which was recommended by Sir Henry De la Beche as the building-stone of the Houses of Parliament; and had his advice not been departed from, by resorting to the Anstone quarries in Yorkshire, the beautiful freestone of Mansfield would, we are persuaded, have been through ages unaffected even in our London atmosphere. The sandy varieties of the Magnesian Limestones of Nottinghamshire were long ago well described by Prof. Sedgwick, and recently their analyses were given in the Memoirs of the Geological Survey, in Mr. Aveline's description of the Quarter-sheets N.E. 71 and S.E. 82.

We may, indeed, adopt the view of synchronizing the red marls and sand-beds which overlie the Magnesian Limestone of Nottinghamshire with the St. Bees and Corby Sandstones of the north-west; and in this way, though the thickness of the Nottinghamshire band is small, it has been clearly represented in the Geological Maps of the north and south of Mansfield by Mr. Aveline, and even there we have thus a tripartite arrangement of the group. In Ireland, also, it is probable that the Upper Permian is represented by the red sandstones which at Rhone Hill, near Duncannon, co. Tyrone, afford Palæoniscus catopterus (Ag.); for these beds have an intimate relation in mineral nature to the St. Bees and Corby Sandstones.

However this may be, we simply call attention to the fact that on the western side of the axis of the north of England, or Pennine Chain, the Permian Group, from its base to its summit, consists of a triplex conformable series similar to that which was long ago described by one of us as prevailing over wide tracts of the Continent of Europe.

The establishment of a vast range of Permian rocks in the northwest of England is connected with the probability that productive Carboniferous deposits will at a future day be attained by sinking through some of the superjacent Red Sandstones. Near Barrowmouth, at St. Bees Head, coal has been indeed worked for many years under the Magnesian Limestone, the Lower Permian having there become very thin; and we see no reason why coal may not be found, though at greater depths, under the Red Sandstone north-west of the village of St. Bees. Again, immediately south of Maryport, where the productive coal-measures dip northwards, they are flanked on the north by the Upper Permian, from which they are separated by the powerful fault before alluded to. Now, if the Lower Permian should have become thin here, as it has done in the environs of Whitehaven, coal may very well be won by shafts sunk through the Upper Permian Sandstones. Lastly, the small but highly productive coal-field of Cannoby, lying on the northern side of the great Pennine fault in its extension into Scotland, is seen to have its strata dipping southward, or directly towards the Corby Sandstones or Upper Permian. We have therefore little doubt that, at a depth which we will not pretend to estimate, the coal-beds of Cannoby, which have been abruptly broken off by the great downcast fault extending under the Red Permian Rocks, and under the Solway Frith, may in this way be viewed as the north-eastern limb of the West Cumberland or Whitehaven coal-field.

PROCEEDINGS

OF

THE GEOLOGICAL SOCIETY.

POSTPONED PAPER.

A MONOGRAPH of the AMMONITES of the CAMBRIDGE GREENSAND. By HARRY SEELEY, Esq., F.G.S., Woodwardian Museum.

[Read June 17, 1863*.]

[This paper was withdrawn by permission of the Council.]

(Abstract.)

In this paper the Ammonites and Scaphites of the Cambridge Coprolite-bed were described, with the endeavour to elucidate the nature of Ammonite-species in a single stratum and a limited area. It was the result of five years' study of about 12,000 specimens.

The special peculiarity of the paper was that many "species hitherto thought distinct were connected together. This was called "resolving species into the varieties of which they appear to consist." The specific names became varietal, "the idea of the system followed being to make certain forms the indices as it were to their groups," without disturbing the existing nomenclature.

There are three "great species," or groups, called Ammonites rostratus, A. splendens, and A. planulatus; and a few "small species," mostly new; besides these were a small group of Scaphites, and a Crioceras from Hunstanton.

Every recognizable variation of form was described, and, in a few marked instances, named, the named forms being merely used as necessary links for connecting together allied species.

In the "splendens group," A. Fittoni was shown to pass insensibly into A. splendens. A. splendens was traced on the one hand through a series of variations into a thick and robust, ribbed, and tubercled new species called A. cratus; and this again was regarded as passing into another new form, very thin and flat, called A. leptus. And, on the other hand, A. splendens was traced into A. Guersantii, and A. Guersantii into A. Renausianus, and this again into another new form called A. gymnus. A. Guersantii passed into A. auritus ; this species passed into a new form called A. novatus; this into

For the other communications read at this Evening-meeting, see Quart. Journ. Geol. Soc. vol. xix. p. 506, and vol. xx. p. 74.

A. Raulinianus; and that into a new ribless, tubercled form called A. tetragonus. A. novatus passed into another new form called A. dendronotus, very like A. cratus and A. interruptus. A. novatus also passes into A. Salteri, as well as into A. Vraconensis, which latter may be traced into A. Studeri. All these forms were considered to make up, in the Cambridge district, one great natural species, called the "splendens "-group. And the author has fortified his conclusions by breaking up many specimens, and finding the inner whorls corresponding to those of other species. Thus, A. splendens is found in the interior of A. auritus; A. Studeri may be extracted from A. Raulinianus; and A. splendens and A. Studeri differ only essentially in the degree of inflation and roughness of ribbing. The "rostratus" and "planulatus" groups were similarly described. The former consists of the South of England A. rostratus, the Cambridge "rostratus" (A. symmetricus), two other varieties (new), and a variation from A. inflatus, called A. pachys; the latter contains A. Timotheanus (Pictet, non Mayor), A. planulatus, A. Mayorianus, A. octosulcatus, and A. latidorsatus.

The "small species" described were A. cœlonotus (new), which is a variation from A. falcatus, in which the ribs are not angulated, but have a slight sigmoidal flexure. A. Woodwardi (new), like a young A. Studeri, only the ribs pass over the back. A. glossonotus (new), in which two ribs unite to pass over and form a tongue-like expansion on the back. A. sexangularis (new), with few and strong ribs, and three rows of tubercles on the angulated back; the sides are flat and the umbilicus small. A. rhaphonotus (new), which is a similar shell, with a round back, crenulated, with one row of small tubercles, and crossed by more numerous and finer ribs. An untuberculated, round-backed variety of A. navicularis, called A. nothus; also A. Wiesti, and some few others.

The Scaphites is S. æqualis, and shows variation in size, form, and ornament, the latter being the addition of a row of tubercles on each side of the hamus.

The Crioceras is C. occultus, in which the tetragonal whorl, margined on each side of the back with a row of tubercles, is so coiled as almost to overlap the whorl beneath.

The biological and geological considerations arising out of the facts detailed in the paper were reserved.

DONATIONS

TO THE

LIBRARY OF THE GEOLOGICAL SOCIETY.

From October 1st to December 31st, 1863.

I. TRANSACTIONS AND JOURNALS.

Presented by the respective Societies and Editors.

American Journal of Science and Arts.

Second Series. Vol. xxxvi.

Nos. 107 & 108. September and November 1863. From Prof. B. Silliman, For. Mem. G.S.

J. P. Lesley.-Coal-measures of Cape Breton, N.B., 179.

T. Sterry Hunt.-Chemical and Mineralogical Relations of Metamorphic Rocks, 214.

J. D. Dana. Appalachians and Rocky Mountains as Time-boundaries in Geological History, 227.

E. Billings. On the genus Centronella, 236.

G. J. Brush.-Childrenite from Hebron, Maine, 257.

J. P. Cooke.-Crystallographic Examination of the Hebron Mineral,
258.

C. T. Jackson. Meteoric Iron from Dakota Territory, 259.
Natural History and Geology of the State of Maine, 274.

Quarterly Journal of the Geological Society, Extracts from, 277.
Rose.-Production of crystalline limestone by heat, 278.

W. E. Logan.-Rocks of the Quebec Group at Point Lévis, 366.
T. S. Hunt.-Earth's Climate in Palæozoic Times, 396.
Discovery of Fossil Man, 402.

T. L. Phipson.-Phosphatic (or guano) rock from the Island of Som-
brero, West Indies, 423.

A. A. Julien.-Observations on the Sombrero Guano, 424.

T. S. Hunt. On the Nature of Jade, and on a new mineral species described by M. Damour, 426.

Report of Progress of the Geological Survey of Canada, 428.

J. W. Dawson.-Air-breathers of the Coal Period, 430.

O. Buchner's 'Die Meteoriten, ihre Geschichte, mineralogische und chemische Beschaffenheit,' noticed, 445,