34 mk. t. e. jamiesois t on the [Feb. 1906, 



This Clara bed is covered by a great thick sheet of Boulder-Clay, 

 showing that intense Glacial conditions must have supervened after 

 the shells were laid down ; but the occurrence of marine mollusca 

 there shows that at the time when they lived, the mass of ice which 

 formerly filled the basin of the Moray Firth must have melted away 

 as far at least as Inverness, at the head of the Firth. This is 

 further proved by a remnant of shelly silt which I observed at 

 Ardersier, near Fort George, 10 miles north-east of Inverness. The 

 prevailing shell in it was Astarte sulcata, but I found, also Leda 

 pernula, and a specimen of Tellina which seemed to be T. proscima 

 of Brown. The shells had been entire and showed the epidermis, 

 but were much crushed and decayed, so that it was scarcely possible 

 to get them out in a state suitable for examination. The silt con- 

 taining them was very hard, as if it had been heavily pressed, and 

 was unconformably enveloped by a mass of unfossiliferous Drift of 

 quite a -different colour and character. 



XY. The Daek-Bltje Clay oe the Baneeshiee Coast 



AND NoETHEBN AbEEDEENSHIKE. 



The clay-beds found along the northern coast of Aberdeen and 

 Banff are generally of a dark bluish tint, often nearly black when 

 wet. This colour of clay extends from Fraserburgh sporadically 

 all the way west to Cullen, near where is a bed of it at Tochineal, 

 which has been worked for tiles for many years. A little to the 

 east of Portsoy, I noticed remains of Arctic shells scantily dispersed 

 in this dark clay along the high banks facing the sea. These shells 

 were in a more or less broken state. The only species that I could 

 make out were Tellina provima, T. solidida, Astarte borealis, and 

 Leda pemida. The mass of clay resting upon the rock was about 

 30 feet thick, mostly all of a dark indigo tint, without appearance 

 of stratification. Near the top it was browner in colour, with more 

 stones and even some big boulders, but no shells. 



This dark indigo-coloured clay often contains Jurassic fossils, 

 which may have been derived from strata existing somewhere in 

 the basin of the Moray Firth ; and at Moreseat, in Aberdeenshire, 

 debris of the Greensand occurs in a dark friable clay, possibly of 

 the same age. This dark clay, however, does not seem to be the 

 product of the last ice-sheet, for it is covered at Moreseat and 

 elsewhere by a later Drift of a brow T nish or reddish tint. 



On the estate of Cairnfield, to the south of Buckie, Mr. T. D. 

 Wallace (of Inverness) noticed that the dark bluish-black clay was 

 covered by red Boulder-Clay; and Mr. Martin (of Elgin) mentions 

 that, on the eastern slope of Coulert Hill, near Lossiemouth, red 

 Boulder-Clay wraps round a bed of fine blue clay containing 

 belemnites and other Oolitic fossils. Mr. John Milne at Atherb 

 also remarked that the ice-sheet which brought the blue fossiliferous 

 clay must have come first, as it is always lowest, the red or yellow 

 clay when present lying above it : such, indeed, is the case near 

 Brucklay Castle. 



