THE OLD RED SANDSTONE. 245 
Quite the reverse. Mark how thickly these carbonaceous 
impressions cover the muddy-colored and fissile sandstones 
of the formation, giving evidence of an abundant vegetation. 
We may learn frorn these obscure markings, that the place 
in which they grew could have been no unfit habitat for the 
crustaceous tribes. 
There is a little, land-locked bay on the southern shore of 
the Frith of Cromarty, effectually screened from the easterly 
winds by the promontory on which the town is built, and but 
little affected by those of any other quarter, from the proxim- 
ity of the neighboring shores. The bottom, at low ebb, pre- 
sents a level plain of sand, so thickly covered by the green 
grass-weed of our more sheltered sandy bays and estuaries, 
chat it presents almost the appearance of a meadow. The 
roots penetrate the sand to the depth of nearly a foot, binding 
it firmly together; and as they have grown and decayed in it 
for centuries, it has acquired, from the disseminated particles 
of vegetable matter, a deep leaden tint, more nearly ap- 
proaching to black than even the dark gray mudstones of 
Balruddery. Nor is this the only effect: the intertwisted 
fibres impart to it such coherence, that, where scooped out 
into pools, the edges stand up perpendicular from the water, 
like banks of clay; and where these are hollowed into cave- 
like recesses, —and there are few of them that are not so 
hollowed, — the recesses remain unbroken and unfilled for 
years. The weeds have imparted to the sand a character 
different from its own, and have rendered it a suitable hab- 
itat for numerous tribes, which, in other circumstances, would 
have found no shelter in it. Now, among these we find in 
abundance the larger crustaceans of our coasts. The brown 
edible crab harbors in the hollows beside the pools; occasion- 
ally we may find in them an overgrown lobster, studded with 
