394 



James Geilde — Discovery of Bos pnmigenius 



tain whether a slip from the hill-side might not explain their inter- 

 stratified position ; but after a minute examination, I was satisfied 

 that no such land-slip had taken place., but that, as I have shown in 

 the sketch-sections, the laminated clay and sand are distinctly inter- 

 bedded with the till. This till is a stifi", hard, dark-brown clay, full 

 of scratched stones, and rests on a much grooved and well-polished 

 surface of porphyritc, — the stri^ running parallel with and up the 

 valley, i.e. to the south-west. The stones have travelled no great 

 distance, but here and there, one may detect a fragment of mica 

 schist, gneiss, quartz-rock, and Old Eed Sandstone — showing that the 

 moraine matter has been amassed during the passage of the glacier 

 from north to south. I noticed no material difference between the 

 till which overlies and that which is overlaid by the stratified de- 

 posits. The former contains a few lenticular nests of earthy sand 

 and gravel, which I did not observe in the latter ; but there is not 

 so much of this last exposed ; and, moreover, as geologists know, the 

 occurrence of such '' nests " is common enough in the Scottish lower 

 Boulder-clay. 



The valley in which these deposits are met with is a remarkable 

 one in its way. The denuding forces which scooped it out have 

 acted along the line of a large fault bearing S.W. to N.E., and conse- 

 quently the narrow hollow extends in a nearly straight direction 

 from the neighbourhood of Caldwell-house to Barrhead, a manu- 

 facturing place, about eight miles south-west from Glasgow. The 

 southern end of the hollow is partly occupied by a small lake (Loch 

 Libo), now much reduced in size as may be seen from the extent 

 of the surrounding alluvium, and the water drains towards the south 

 into the Lugton. But from Shillford (a toll-bar about half-way be- 

 tween Caldwell and Crofthead) the water drains to the north. It 

 was in this northern division of the hollow, in the valley of the 

 Cowdon Burn, near the farm-steading of Millthird, at a height of 

 nearly 500 feet above the sea, where the remains of the Bos primi- 

 genius were found. 



Fig. 1. Sketch- section exposed in the new raihvay-cutting near Crofthead, 

 S.W. Renfrewshire. N.E. 



fli. stiff hard dark brown till full of scratched stones, and resting on striated surface of porphyrite. 



«2, Till of much the same character, but containing a few "nests" of sand and gravel. 



b. Soft clay, interlaminated -with sand, and containing occasional beds of sand and fine gravel. 



p. Ice-worn mass of rock (porphyritc) against which the beds b have been deposited. 



X. Position of the skull of Bos primige7iius. 



r. Present level of railway cutting. 



The sketch- section (Fig. 1) is that which was laid bare at the time 

 I visited the cutting ; of course it runs parallel with the valley. The 

 succession of events, as I read it, is as follows : — First, a glacier 

 ascends the valley, polishing and striating the underlying rocks, and 

 eventually covering them over with its moraine profonde. I need 



