OF SCOTLAND.

365

not yet been detected in Scotland to the north of the MorayFrith ; and its richest British deposits are to be found inMoray, f’erthshire, Fife , Berwickshire, and Ayr. In thecollection of fishes from Dura Den, exhibited four years agobefore 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 restrictingsome of the genera of the formation already named andfigured. It will be found, for instance, that Agassiz’s genusPlacothorax, and his two species Coccosteus maximus andPterichthys major, will ultimately all resolve themselves intothe latter species alone,— Pterichthys major ; —of which, bythe way, vast numbers have recently been found, though ina broken state, in the Upper Old Bed Sandstone of theHeads of Ayr.” We may of course expect, however, tosee more species and genera added to the group than sub-tracted from it. I must mention, ere concluding this partof my subject, a curious fact connected with the flora of theformation. When visiting last spring the Museum of Eco-nomic Geology in Jermyn Street, under the friendly guidanceof the late Professor Edward Forbes , he pointed out to mean interesting group of plants, in a fine state of keeping,which had been derived from the Old Bed Sandstone of Ire­ land . The genera seemed identical with those of the CoalMeasures, but all the species were different. I marked,among the others, an elegant Cyclopterus,— Cyclopterus Hi-bemicus, —of which Sir Boderick Murchison figures a singlepinna in his recently published “ Siluria.” The Professoralso introduced me to the only ichthyic organism that hadbeen found in the Irish deposit, with the plants, a ganoidalfish, apparently a Celacanth, and very much of the type ofthose of the Upper formation, though I failed to identify thespecies with any of those already known. Professor Forbes ,in return, visited my collection here only a few weeks ago •