our former paper[1] on the great Paradoxides such pleurae were described of great length. In the present species they are shorter, but still appear to be distinctly separated by simple grooves from the circular appendix as in P. Davidis. In P. Loveni they are perfectly soldered, and are indicated only by the increased number of lateral grooves and marginal spines of that fossil; and in Anopolenus also the limb is many-ribbed and the margin spinose.—J. W. S.
EXPLANATION OF PLATES II. & III,
(Illustrative of Fossils from the Menevian Group.)
Plate II.
Figs. 1 & 2, 4 & 5. Conocoryphe applanata, Salter. Natural size.
3. perdita, spec. nov. Natural size.
6. Embryo of Conocoryphe applanata. Magnified.
7. Conocoryphe humerosa, Salter. Natural size.
8. bufo, Hicks. Natural size.
9–12. Paradoxides Aurora, Salter.
Plate III.
Paradoxides Hicksii, Salter.
4. On Quaternary Gravels. By A. Tylor, F.G.S.
(Read May 6, 1868[2])
[Plates IV.–IX.]
In continuation of a paper on this subject in the Quart. Journ. Geol. Soc. vol. xxiv. p. 103, I now submit a number of measured sections selected as instances of the deposition of gravels of different character under different circumstances both of height above the sea-level and distance from the sea.
The illustrations and remarks in this paper relate to the unfossiliferous gravels of the rivers Taff, Rhondda, and Cynon, in Glamorganshire, South Wales, to those of the Aire, in Yorkshire, and to the fossiliferous gravels and brick-earths of the lower part of the Thames and Lea rivers, in the counties of Kent and Essex.
One section of the fossiliferous gravel of the river Avon, at Salisbury, is given for the purpose of comparison with those of the Thames; and a section across the valley of the Aire, in Yorkshire, is compared with those in the valleys of the Taff and Aire.
A map of part of Glamorganshire, and a longitudinal section of the bed of the river Taff, with the heights along its course measured above the height of spring tides at Cardiff, have been prepared to define the exact locality of the Welsh gravels alluded to. A similar map and sections of the course of the river Aire, in Yorkshire, with heights measured from the Ordnance datum, are given for comparison with the Welsh illustrations.
A sketch-map of part of the river Thames, and of the adjoining
