122 THE OLD RED SANDSTONE. 
of an Osteolepis, the thorn-like spine of a Cheiracanthus, and 
a Coccosteus well nigh entire. I had at length, after a search 
of nearly ten years, found the true place of the ichthyolite 
bed. The reader may smile, but 1 hope the smile will be a 
good-natured one; a simple pleasure may be not the less sin- 
cere on account of its simplicity ; and ‘ little things are great 
to little men.” I passed over and over the strata, and found 
there could be no mistake. ‘The place of the fossil fish in 
the scale is little more than a hundred feet above the top, and 
not much more than a hundred yards above the base of the 
great conglomerate ; and there lie over it in this section about 
five hundred feet of soft, arenaceous stone, with here and 
there alternating bands of limestone and beds of clay studded 
with nodules—all belonging to the inferior Old Red Sand- 
stone. 
The enormous depth of the Old Red Sandstone of Eng 
land has been divided by Mr. Murchison into three members, 
or formations — the division adopted in his Elements by Mr. 
Lyell, as quoted in an early chapter. ‘These are, the lowest, 
or Tilestone formation, the middle, or Cornstone formation. 
and the uppermost, or Quartzose conglomerate formation. 
The terms are derived from mineralogical characters, and in- 
adequate as designations, therefore, like that of the Old Red 
Sandstone itself, which, in many of its deposits, is not sand- 
stone, and is not red. But they serve to express great natural 
divisions. Now the Tilestone member of England repre- 
sents, as I have already stated, this Lower Old Red Sand- 
stone formation of Scotland; but its extent of vertical de- 
velopment, compared with that of the other two members of 
the system, is strikingly different in the two countries. The 
Tilestones compose the least of the three divisions in Eng- 
land; their representative in Scotland forms by much the 
