and horizontal; they form large and small cells, the first being broad, and the last high. Reproduction by extracalicular gemmation and by fissiparity. Breadth of the corallites at the base from 1 line to 2 lines, and at the calicular surface from to inch. Height of the corallites 3 inches, and depth of the fossa about 14 line. There are three dissepiments to a line.

This species is characterized by the polygonal and irregular shape of the calices, the rudimentary columella, the incomplete third cycle, the transverse and horizontal epitheca reaching very high up, the presence of corallites undergoing fissiparous growth, and the intercostal pits. The perforated state of the smaller lamina is the only Cyphastræan peculiarity; and the species is closely allied to, but is smaller than, Astræa (Heliastraa) quadrangularis, Edwards and Haime, the habitat of which is unfortunately unknown. The amount of endotheca approximates the form to those of the Miocene; but there are none other than generic resemblances to the only known Eocene Astræan.

The perforated laminae of Astroa Defranci (Miocene) resemble those of this species, but the abundant endothecal tissue of the latter forms a specific distinction.-P. M. D.]

EXPLANATION OF PLATES VI. & VII.

Illustrative of Tertiary Shells from Java.

[The figures are of the natural size, unless it is otherwise stated.]

PLATE VI.

Fig. 1. Murex Grooti: a, back view; b, front view.

2.

-? paradoxicus: a, spinous variety, back view; b, ordinary form, front view.

3. Pyrula Javanis: a, front view; b, back view.

4.

cochlidium; front view.

simplex.

3. Conus striatellus: a, front view; b, portion of the side, magnified 4

diameters.

4. Oliva utriculus (juv.?); front view.

5. Vicarya (?) callosa; front view.

6. Turbo obliquus; front view.

7. Cardium subalternatum: a, lateral view of right valve; b, view of anterior extremity.

8. Pythina Semperi: a, exterior of left valve; b, exterior of right valve; both magnified 3 diameters.

9. Astræa Herklotsi: a, calice, magnified 4 diameters; b, transverse section of a corallite, magnified 3 diameters; c, longitudinal section of a corallite, magnified 4 diameters, showing the walls, the laminæ, the endothecal dissepiments across the laminæ, the central columellar false pali, and the exotheca; d, diagram of the superior margin of a septum showing the paliform tooth.

74

PROCEEDINGS

OF

THE GEOLOGICAL SOCIETY.

POSTPONED PAPER.

On the SANDSTONES and SHALES of the OOLITES of SCARBOROUGH, with DESCRIPTIONS of some NEW SPECIES of FOSSIL PLANTS. By JOHN LECKENBY, Esq., F.G.S.

(Read June 17, 1863*.)

[PLATES VIII.-XI.]

I. DESCRIPTION OF THE BEDS.

THE "Grey Limestone" of Scarborough, and its associated and alternating beds of sandstone and shale, have lately attracted the attention of geologists from other parts of England, who, aided by their knowledge of the Oolites of their own districts, and of France and Germany, have done much to establish more accurate views of the correlations of the Yorkshire beds.

I do not, therefore, hope to add much to the general information which is now possessed as to the true position of the fossil plantyielding beds at Gristhorpe Bay, Cloughton Wyke, and the neighbourhood of Whitby; my chief intention being to describe and figure some new or imperfectly known species, and to point out certain affinities and differences that have hitherto escaped detection.

Prof. Williamson, in a paper communicated to the Geological Society in 1839†, first pointed out the true position of the famous plant-bed at Gristhorpe Bay, below the Grey Limestone; and, in 1859, his views were confirmed by Dr. Wright, the subject being considerably amplified in a paper read by the latter author before the Geological Society in April of that year. I have only to add, in confirmation of these opinions, a fact which is not made sufficiently prominent in Dr. Wright's paper, that from the first appearance of the "Grey Limestone" in the north corner of Gristhorpe Bay, through

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

+ Trans. Geol. Soc. 2nd ser. vol. vi. part 1. p. 143, 1841.

Quart. Journ. Geol. Soc. vol. xvi. p. 1, 1860.

out its entire course, both on the south and to the north of Searborough, on the coast, and in the interior, it is uniformly based upon a bed of freestone (No. 11, Dr. Wright's memoir, p. 30). Wherever the "Grey Limestone" is found in Yorkshire, this bed, well known to local geologists, will be found in immediate underlying contact, and all the fossil Plants of Gristhorpe are found in a bed many feet below it.

Thus it follows that all the Plants hitherto referred to the "Upper Sandstone, Shale, and Coal," and figured in plates 7 & 8 of the 'Illustrations of the Geology of Yorkshire,' belong to the "Lower Sandstones and Shales." They occupy at Gristhorpe the same zone as at Cloughton Wyke, and the Table on p. 76 shows how little difference really exists in the respective floras of the two localities.

I believe the error to have originated in the fact of the thin, attenuated edges of the bed of Grey Limestone in Gristhorpe Bay having been for a long time overlooked, and only first detected by Prof. Williamson,-the bed No. 21 of Dr. Wright's memoir (p. 31) having been previously supposed to be the first indication of marine conditions below the Cornbrash,-the truth being that the entire series, from the Inferior Oolite upwards to the Cornbrash, is in Yorkshire a frequent succession of marine and freshwater conditions, the alternations not being fewer than ten in number.

Hitherto but few Plants have been found in the true Upper Sandstones and Shales overlying the "Grey Limestone." Traces of other species sometimes occur; but the only definite form that I am acquainted with from these beds is the Cyclopteris digitata, Fossil Flora, tab. 66 (Cyclopteris Huttoni of Sternberg and Morris). This is not the Cyclopteris digitata of Brongniart; the two species being distinct, as was first pointed out by Sir C. J. F. Bunbury, in his paper on the Fossil Plants of Scarborough, published in the Proceedings of the Geological Society,' March 1851. It is rather abundant in a white, fine-grained sandstone (bed No.7, p. 28, Dr. Wright's memoir), showing the blackened leaves in fine contrast. Although not uncommon at White Nab, south of Scarborough, it is more frequently obtained in the same zone a little to the north of the town. Hence specimens in collections have been always referred to the "Lower Sandstone and Shale." I am not aware that it occurs in the "Lower Sandstone and Shale" at all, although referred to this stratum by Sir C. J. F. Bunbury (p. 184), he having been doubtless misled by the labels in the collections which he examined at Scarborough.

Along the course of the "Upper Sandstones and Shales," between the Spa and White Nab, the geologist may examine with interest the remains of the bed of an extensive freshwater lake, whose bottom has been a living mass of Unioniform Shells; they are all placed endwise and closely impacted, but exist only as casts, with rarely traces of their shelly exterior. In some instances, the entombing rock being harder than the mud which formed their bed, the latter has perished, and in caves by the sea-side the Uniones may be seen depending from the rock above.

In the following list of Plants from the beds at Gristhorpe and Cloughton, I have distinguished as follows

a. Those hitherto found only at Gristhorpe. b. Those found only at Cloughton.

c. Those common to both localities.

Of the species quoted above, all the moderately plentiful ones occur both at Gristhorpe and Cloughton. It is only in the case of such as are of really rare occurrence that I can quote but one locality. Further researches will probably increase the number of species common to both.

The Millepore-bed referred by Prof. Phillips (at page 51, Geology of Yorkshire') to the Inferior Oolite, and described by Dr. Wright (No. 26, page 31) in the memoir already referred to, is the lowest marine bed of the series, but there are at least 250 feet of sandstones and shales between it and the true Inferior Oolite or Dogger. It derives its name from the abundance of Cricopora straminea (Millepora straminea, Phillips) which is displayed upon its weathered lateral surfaces. It is the hardest rock of the series, and its superior resistance to the action of the waves is shown in rugged reefs along the shore.

Below this bed the flora is characterized by the greater preponderance of the genera Zamia and Otopteris; as we ascend these genera become, on the contrary, rarer, their place being occupied by an abundance of Pterophyllum. In the following list of species below the Millepore-bed, those marked b have not hitherto been found above it.