308 MR "ROBERT KIDSTON ON THE FOSSIL PLANTS OF THE 



same terms, for the same rocks, whether occurring in England or Scotland; and the 

 loose manner in which the terms Upper and Lower Coal Measures are used by some 

 sxeolojnsts has led to needless confusion in the correlation of the British Coal Measures. 

 On the other hand, it is most desirable that the two series of the Lower Coal Measures 

 should be clearly distinguished, but this is easily done by adopting the terms Upper 

 and Lower Series to the two groups composing our Lower Coal Measures, and I hope 

 that local geologists will adopt these or similar terms, and entirely give up the misleading 

 designations of Upper and Lower Coal Measures when speaking of the two series of the 

 Scotch Lower Coal Measures. 



All the species recorded in this paper (with the exception of Stigmaria stettata) are 

 from the Lower Series of the Lower Coal Measures. 



There are two chief centres of mining operations in this portion of the Ayrshire Coal 

 Measures, generally known as the Kilmarnock and Galston and the Kilwinning Coal Fields. 

 These two districts form part of the same coal field, and many of the seams are common 

 to both areas, though frequently going under different names, the names having been 

 given before the seams were correlated. 



As usually found in all coal fields, and even in those of limited extent, certain seams 

 workable at one point split up and become too thin to work, or entirely die out, in another 

 part of the same coal field, and such cases are seen here. 



I give five vertical sections from different parts of the coal field, which show the 

 position of the principal coal seams, and from which can also be learnt the general 

 structure of the district, and the principal names that have been applied to the various 

 coal seams (see Table). 



The section of No. 1 pit, Windyedge, Kilmarnock, has been given me by Mr Hugh 

 S. Dunn, jr., Kilmarnock. 



The general section of the Kilwinning Coal Field has been prepared by Mr J. Smith, 

 Kilwinning. 



The Annandale Colliery section has been communicated by Mr J. Rorrison, Springhill. 



The section of strata in No. 6 pit, Bonnyton Colliery, near Kilmarnock, was procured 

 for me by Mr A. Sinclair, Riccarton. 



The section of No. 1 pit, Grange, was kindly supplied to me by Mr Yates, and in 

 the letter from Mr Geo. H. Geddes which accompanied it, it is stated that no regular 

 journal was kept during the sinking of the pit, which explains the term used, " mixed 

 strata." 



The great thickness of boulder clay and of sand and gravel are a peculiar feature in 

 this pit, as well as the red sandstone above the coals. Mr Geddes further states, that 

 he is not sure that it is correct to say that the whole of the 300 feet of red sandstone 

 and faikes, lying between the sand and gravel, is one bed of sandstone with faikes in the 

 lower part of it ; but in any case, the sandstone bed is of great thickness. 



The sand and gravel and this red sandstone were the cause of much expense in sinking 

 through them on account of the water they gave off. 



