190 Proceedings of the Royal Society of Edinburgh. [Sess. 
Hurlet District. Carluke District. 
Baldernock Limestone. 
Blackbyre Limestone .... Main Limestone. 
Holly bush Sandstone. 
Hollvbush Limestone .... Productus giganteus Limestone. 
VII. Sections between Cobbinshaw and the Firth of Forth. 
The Lower Limestone Series having been traced pari passu from 
the Hurlet Section eastwards through East Kilbride and Carluke to the 
neighbourhood of Wilsontown in the Clyde drainage area, we cross the 
watershed and enter the Forth basin at Cobbinshaw Reservoir, from which 
point the Lower Limestone Series may be traced by Baads Mill, Addiewell, 
Blackburn, over the Bathgate Hills to the shores of the Firth of Forth 
at Carriden. Between Bathgate and the Firth of Forth the sequence is 
considerably obscured by the intercalation of thick beds of lava, amongst 
which, however, certain well-marked limestone horizons can be more or 
less continuously followed. 
Near Cobbinshaw Reservoir a pit is at present being worked by the 
Pumpherston Oil Company, in which there is a 2 -feet limestone underlain 
by dark blaes carrying the Hurlet Alum Shale fauna. The state of 
preservation of the fossils in the Alum Shale at this locality has a striking 
resemblance to that exposed at Glen Wynd, near Campsie. They occur 
in loose blocks at the mouth of the pit, and the order of the superposition 
of the various bands has not yet been determined. Between the pit and 
the south end of Cobbinshaw Reservoir the coal and limestone were 
formerly wrought in a mine, and a small section showing the coal, limestone, 
and intervening strata can still be seen at the surface. The coal has 
also been worked at Viewfield Pit further to the south, and the shale 
which lies between the coal and limestone at these three localities has 
yielded the characteristic Hurlet Alum Shale fauna. 
The crop of the Hurlet Limestone can be traced by workings across 
to Baads Mill on the Harwood Burn, and thence to Addiewell Bridge 
on the Breich Water. As the section seen in the Breich Water and its 
tributary, the Skolie Burn, is the most continuous in this part of the 
country, and as it can be linked up both stratigraphically and paleonto- 
logically with those of the West of Scotland, we now describe it in some 
detail. The section exposed is as follows : — 
