542 Geological Society. 



among the Cromarty specimens. Mr. Murchison has given further 

 proof of the age of the Caithness beds by showing that the Dipterus 

 macrolepidotus so common in them, is found also in the tilestone or 

 lowest member of the old red sandstone of England. 



Dr. Malcolmson then proceeds to describe the discoveries recently 

 made by himself, the Rev. G. Gordon, and Mr. Staples, of fossil 

 fishes in a district of old red sandstone, extending from the village 

 of Buckie, near CuUen, to Culloden Moor, 6 miles south of Inver- 

 ness. The southern parts of this tract are occupied by primary 

 rocks, which send off spurs and transverse ridges into the sandstone 

 country, and they are likewise exposed in diflferent places within 

 its area. Wherever the contact of the two classes of rocks is 

 exhibited, the old red sandstone rests on the edges of the older 

 formations, dipping 8° or 12° a little west of north. The granite 

 series also terminate at the junction with the sandstones. The old 

 red sandstone Dr. Malcolmson divides into three portions, the lowest 

 of which he calls the Inferior or Great Conglomerate ; the middle, 

 the Central or Cornstone division ; and the uppermost, the Fine 

 Grain Sandstone and Quartzose Conglomerate. 



The lowest division is shown to belong to the great conglomerate 

 at the base of the old red sandstone of Sutherland and Ross. The 

 beds of which it consists are exposed in ravines on the right bank 

 of the Nairn to the east of Inverness, also in the ravines above 

 Cawdor Castle ; but at Rait Castle they thin out, or were denu- 

 dated, according to the author's view, before the deposition of the 

 upper beds. On the east side of the hill of Rait they reappear, 

 and extend along the Burn of Lethen for several miles. They occur 

 also at Binnie in the vale of Rothes, south of Elgin, and along the 

 Spey. The division consists of partially-rounded fragments of the 

 primary rocks of the neighbourhood, cemented by a calcareous and 

 ferruginous sandstone. 



The Cornstone division consists of sandstones, calciferous concre- 

 tions, conglomerates, and marls, and contains scales of the Holopty- 

 clius Nobilissimus and other fishes ; also teeth and ichthyodorulites 

 of new genera. This fossiliferous rock is exposed for a short distance 

 at Scot-craig near Elgin, resting on the great conglomerate, and it 

 passes below the cornstone of Elgin. 



Resting on the Elgin cornstones is a series of very beautiful 

 white and yellow siliceous sandstones, containing pebbles of quartz, 

 gneiss, and granite. It may be traced from Quarry Hill near Elgin, 

 to Burge, 3^ miles east of Forres, extending over a considerable 

 part of the north-eastern district of Murray. 



Dr. Malcolmson next describes, in detail, the cornstone series as 

 it is displayed on the banks of the Findhorn, particularly where it 

 is exposed between the gneiss and the Cothall limestone*, various 

 remains of fish having been found there ; and at Altyn, where he 

 obtained scales of Holoptychus Nobilissimus, and abundance of 



* Dr. Malcolmson refers to Prof. Sedgwick and Mr. Murchison's paper 

 on this district for other information respecting the Cothall hmestone, 

 Geol. Trans., 2nd series., vol. III., p. 151, 



