336 TRANSACTIONS, NATURAL HISTORY SOCIETY OF GLASGOW. 



Conodonts from the Carboniferous Limestone Strata 



of the West of Scotland. By John Smith. {With 

 JVotes on the Specimens and Descriptions of Six New SpecieSj 

 by Geo. Jennings Hinde, Ph.D., F.G.S.) 



[Read 30th May, 1899.] 



In the spring of 1876 I commenced to examine systematically 

 the rotted limestones of Ayrshire. My first samples were from 

 Cunningham Baidland, near Dairy, where the upper bed of the 

 lower limestones was at that time being worked for agricultural 

 purposes. By the action of acids, the limestone on each side of 

 the rock jointings had been dissolved away to the extent of a 

 few inches, the limestone beds having been rotted more or less at 

 their edges, according to the purity or dirtiness of the stone. 

 When the rock was quarried away along one of the master 

 joints the quarry face presented the appearance of shelves of 

 varying depths, and very rugged, owing to the limestone having 

 been very irregularly dissolved. Each shelf contained a small 

 quantity of a rusty-looking powder — the undissolved material of 

 the limestone — and this powder was found to contain minute 

 fossils which had been originally composed more or less of 

 chitinous, phosphatic, or siliceous material, or had afterwards 

 been more or less impregnated with silica.* 



In searching the shales of the Carboniferous limestone for 

 microzoa, our plan had formerly been to rub the material 

 between the hands, for the purpose of removing the shale from 

 the surfaces of the minute organisms. I soon found out that 

 this plan would not do for the rotted limestone debris, for 

 although many of the fossils looked quite complete, still the 

 carbonate of lime they had contained had, in many instances, 

 been sucked out, rendering them very tender. 



* Although this is the usual mode of weathering of limestone, still the 

 limestone in the Glencart section has weathered in a very different 

 manner, the rotted part being full of subglobular cavities, an inch to two 

 or three inches in diameter, the lower half, or even more, containing the 

 undissolved powder. 



