DEPOSITS OF SCOTLAND. 383 
ish deposits are to be found in Moray, Perthshire, Fife, Ber- 
wickshire, and Ayr. In the collection of fishes from Dura 
Den, exhibited four years ago before the British Association, 
then assembled at Edinburgh, I saw several Celacanths that 
have not yet been described; and a good deal has still to be 
done in fixing and restricting some of the genera of the forma- 
tion already named and figured. It will be found, for instance, 
that Agassiz’s genus Placothorax, and his two species Coccos- 
teus maximus and Pterichthys major, will ultimately all resolve 
themselves into the latter species alone, — Pterichthys major ; 
of which, by the way, vast numbers have recently been found, 
though in a broken state, in the Upper Old Red Sandstone of the 
“Yieads of Ayr.” We may of course expect, however, to see 
more species and genera added to the group than subtracted 
from it. I must mention, ere concluding this part of my sub- 
ject, a curious fact connected with the flora of the formation. 
When visiting last spring the Museum of Economic Geology 
in Jermyn-street, under the friendly guidance of the late Pro- 
fessor Edward Forbes, he pointed out to me an interesting 
group of plants, in a fine state of keeping, which had been 
derived from the Old Red Sandstone of Ireland, The genera 
seemed identical with those of the Coal Measures, but all the 
species were different. I marked, among the others, an ele- 
gant Cyclopterus, — Cyclopterus Hibernicus, — of which Sir 
Roderick Murchison figures a single pinna in his recently pub- 
lished “ Siluria.” The Professor also introduced me to the only 
ichthyic organism that had been found in the Irish deposit, with 
the plants, a ganoidal fish, apparently a Celacanth, and very 
much of the type of those of the Upper formation, though I 
failed to identify the species with any of those already known, 
Professor Forbes, in return, visited my collection here only a 
few weeks ago; and, in a fern of this Upper deposit, laid open 
by our ingenious member, Mr. John Stewart, in Prestonhaugh 
