176 Proceedings of the Koyal Society of Edinburgh. [Sess. 
been named the Lower Longcraig Limestone. We believe the third lime- 
stone from the bottom, known as the Upper Longcraig Limestone, to be the 
equivalent of the Hurlet Limestone. 
The map of West Fife, including the Lower Limestones of the coast 
section between Kinghorn and Kirkcaldy, was published in 1867, but 
was not then accompanied by an Explanatory Memoir. In this region the 
Seafield Tower Limestone exposed on the shore section south of Kirkcaldy 
is taken as the Hurlet Limestone, and is regarded as being upon the same 
horizon as the Charlestown Limestone on the north shore of the Firth 
of Forth. 
The Survey Memoir in Explanation of Sheet 22 appeared in 1872,* and 
deals with the Lower Limestone Series in North Ayrshire in the district 
around Beith and Hairy, but in this Memoir no attempt has been made 
at a detailed correlation of the Ayrshire Limestones nor of their relation- 
ship to the Hurlet Series. 
The Explanation to Sheet 23 appeared in 1873, f five years previous to 
the issue of the map of the Hurlet district, and it deals with the members 
of the Lower Limestone Series so well developed in the East Kilbride, 
Strathavon, Lesmahagow, and Carluke districts. A partial attempt is 
made to correlate the various limestones included within the sheet with 
one another, such as the Main Limestone, the Birkfield or first Calmy 
Limestone, the Kingshaw Limestones, and the Calderwood Cement 
throughout the district shown in the map, but no detailed attempt is 
made to correlate them with the limestones of the Hurlet district. It is 
important, however, to note that the Main or Hawthorn Limestone is 
taken as the equivalent of the Carluke Main, the Hurlet Main, Main 
Limestone of Wilsontown and Strathavon districts, Hawthorn Limestone 
of Muirkirk, and No. 2 Limestone of Lesmahagow district. 
The Explanation to Sheet 31 J was published in the year 1879. This 
sheet shows the Lower Limestone Series stretching along the southern part 
of the Campsie and Kilsyth Hills as far as Stirling, and also from the 
neighbourhood of Addiewell through the Bathgate Hills to Linlithgow on 
the east. In the first of these areas, as far east as Corrieburn, near Kilsyth, 
the Hurlet Limestone was correctly identified. In the Explanation to 
Sheet 32 the Tartraven and West Kirkton Limestone was taken as the 
boundary line between the Carboniferous Limestone and Calciferous 
* Memoirs of the Geological Survey , Scotland: Explanation of Sheet 22, Ayrshire , Northern 
District , and Parts of Renfrewshire and Lanarkshire. 
f Ibid., Explanation of Sheet 23, Lanarkshire , Central Districts. 
X Ibid., Explanation of Sheet 31, Lanarkshire N., Stirlingshire S., Linlithgowshire W. 
