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very singular fish, called Pterichthys by Agassiz, long before that 
creature was first understood. Look again to the clear and ge- 
neral view which this author takes of the greatest of Scottish de- 
posits, and how well he conveys to unpractised readers a true idea 
of its position, importance, and diyisions, and you will agree with 
me that in Mr. Hugh Miller we have to hail the accession to geo- 
logical writers of a man highly qualified to advance the science. 
Few persons, and too often least of all those who are, if I may so 
speak, professed geologists, succeed in imparting to others, who have 
not studied the seience, a clear conception of their views. In this 
respect the character of Mr. Miller’s work is admirable, for it por- 
trays the means by which the author acquired his knowledge, and, 
from its persuasive manner, is worth, to a beginner, a thousand di- 
dactic treatises, 
I hoped before now to have seen in print the very valuable me- 
moir prepared by Dr. Malcolmsen long ago, on the divisions and 
development of the Old Red Sandstone in the North of Scotland. 
This delay has been caused solely by the desire that the descrip- 
tion of the various fishes which he has pointed out as character- 
izing the different stages of the deposit should be given by Pro- 
fessor Agassiz. The numerous avoeations in glacial and other geo- 
logical inquiries, as well as, I regret to say, his partial ill health, 
might alone have led us to account for the postponement of this 
labour by M, Agassiz; but in a recent letter to myself he has also 
given the following important reason :—‘‘ When I promised you to 
eccupy myself with the determination of the fossil fishes of Dr. 
Malcolmson, I believed that it would be as easy a task to me as the 
determination of other ichthyolites, and I had no doubt that your 
Devonian system must reveal quite a new world in the class of fishes 
so very different from existing species. The effort has thrown upon 
me the obligation of prodigious labour, to arrive at some precise re- 
sults as to these curious objects; and without giving you something 
very imperfect, which I look upon as yet to be unworthy of pub- 
lication, I must have recourse to your indulgence for the delay.” 
Regretting sincerely that injustice seems to be done to Dr. 
Malcolmson by this delay, I have, I confess, a pleasure in know- 
ing that Professor Agassiz will well investigate all these curious 
animals before he pronounces his final opinion. I can even assure 
him, that strangely formed as these Scottish types may be, he has 
yet to hear of some still more marvellous fishes which the Devonian 
or Old Red system contains in assuining its Russian dress. In that 
empire, where in some mountain tracts the system is black, slaty, and 
erystalline, there are also vast undulations and plains in which it is 
composed of slightly coherent, red, green, and yellow sands, shales, 
and limestones. In some of these beds, near Dorpat, Professor Asmus 
‘has detected. gigantic fishes, which he is now describing; and Mr. 
Pander, so distinguished by his paleontological works on the en- 
virons of St. Petersburgh, is preparing an account of others, some of 
which are specifically identical with those of Scotland. I cannot 
venture to anticipate what these naturalists will shortly lay before 
