Page:Quarterly Journal of the Geological Society of London, vol. 28.djvu/545

1872.] Finally, the Solenastræa I described in Quart. Journ. Geol. Soc. vol. xxvii. p. 369 is probably a remanié fossil. It is remarkable that the present coral fauna of the British seas should be so poorly represented in the Crag deposits.

The resemblance of the new species to Trochocyathus meridionalis, Duncan, of the Australian marine Upper Tertiaries below the horizon of the so-called Pliocene is remarkable; but it probably depends upon the descent of both forms from some unknown Jurassic or Cretaceous ancestor.

Mr. inquired whether the fossil bore any resemblance to any of the French Eocene forms, and whether there was any possibility of its being derivative.

Prof. replied that the specimen was but little worn, and was therefore probably not remanié, though this point was not absolutely certain.



gravels and brick-earths of this part of the Thames valley have been classed by Mr. Prestwich and Mr. Whitaker into two principal groups;—1st, the high-level gravels of Mr. Prestwich, occupying the summits of the hills above the valley; and, 2ndly, the valley-gravels, occupying the sides and bottom of the valley itself.

With respect to the former, or high-level gravels, some slight difference of opinion appears at one time to have existed between the two authorities whom I have quoted—Mr. Prestwich including the gravels upon Wimbledon, Wandsworth, and Clapham Commons amongst the high-level gravels, whilst Mr. Whitaker considers the gravels of Wandsworth and Clapham Commons to belong to the valley-gravels. He, indeed, if I understand rightly his memoir on Sheet 7 of the Geological Survey Map, appears to think it possible that