162 THE OLD RED SANDSTONE. 
though in a state of very imperfect preservation, scales that 
differ from those of the Holoptychius, and from one another. 
One of these, figured and described by Professor Fleming in 
Cheek’s Edinburgh Journal, bearing on its upper surface a 
mark like a St. Andrew’s cross, surrounded by tubercled dot- 
tings, and closely resembling in external appearance some 
of the scales of the common sturgeon, ‘‘ may be referred 
with some probability,” says the Professor, ‘to an extinct 
species of the genus Accipenser.* The deposit, too, abounds 
ently to the influences of an organic law, internal to each, but of 
the operation of some external cause, acting on the whole in one 
direction. 
* May I crave the attention of the reader to a brief statement of 
fact? I have said that Professor Fleming, when he minutely de- 
scribed the scales of the Holoptychius, hazarded no conjecture regard- 
ing the generic character of the creature to which they had belonged ; 
he merely introduced them to the notice of the public as the scales 
of some “‘ vertebrated animal, probably those of a fish.” I now state 
that he described the scales of a contemporary ichthyolite as bearing, 
in external appearance, a ‘‘ close resemblance to some of the scales of 
the common sturgeon.” It has been asserted, that it was the scales 
of the Holoptychius which he thus described, “referring them to an 
extinct species of the genus Accipenser ;’’? and the assertion has been 
extensively credited, and by some of our highest geological authori- 
ties. Agassiz himself, evidently in the belief that the professor had 
fallen into a palpable error, deems it necessary to prove that the 
Holoptychius could have borne ‘‘no relation to the Accipenser or stur- 
geon.” Mr. Murchison, in his Silurian System, refers also to the sup- 
posed mistake. The person with whom the misunderstanding seems 
to have originated is the Rey. Dr. Anderson, of Newburgh. About 
a twelvemonth after the discovery of Professor Fleming in the sand- 
stones of Drumdryan, a similar discovery was made in the sandstones 
of Clashbennie by a geologist of Perth, who, on submitting his new 
found scales to Dr. Anderson, concluded, with the Doctor, that they 
