Crossword-Solution: TILESTONES 10 letters, 1 clue 🏆 scrabble score: 10

The fishes of this lowest English Old Red are _Cephalaspis_ and _Pteraspis,_ specifically different from species of the same genera which occur in the uppermost Ludlow or Silurian tilestones.

Murchison to the Old Red Sandstone, under the name of “Tilestones.” In mineral character this group forms a transition from the Silurian to the Old Red Sandstone, the strata of both being conformable; but it is now ascertained that the fossils agree in great part specifically, and in general character entirely, with those of the underlying Upper Ludlow rocks.

This formation of the gray tilestones has furnished one vegetable organism apparently higher in the scale than those just described, in a well marked Lepidodendron, which exhibits, like the Araucarian of the Lower Old Red, though less distinctly, the internal structure.

And such are some of the considerations that still lead me, notwithstanding the failure of previous evidence, to hold, at least, provisionally, that our Scottish flagstones to the north of the Grampians occupy a lower horizon than our Scottish tilestones to the south.

The crustaceans of the upper Silurian of Lesmahagow, too, seem certainly much akin to those of the Forfarshire tilestones.] [Illustration: Fig.