340 TRANSACTIONS, NATURAL HISTORY SOCIETY OF GLASGOW. 



Conodonts are to be ascribed to the Vertebrate or Invertebrate 

 sub-kingdoms. If they belonged to any division of the Inverte- 

 brata their size, form, and appearance would point towards the 

 MoUusca, but the dental apparatus of existing forms of this 

 division is siliceous, whereas the Conodonts are calcareous in 

 their chemical composition. Besides, no Gasteropoda of sufficient 

 size to have had lingual teeth of the dimensions of the Conodonts 

 are found in the same beds with them, and it does not appear 

 likely that naked forms of Mollusca would exist in any numbers 

 without being accompanied by shell-bearing forms. It is 

 interesting to note, however, that in these Ayrshire Carboniferous 

 strata, as well as in America and Russia, the Conodonts are 

 found associated with numerous undoubted fish teeth and scales 

 of fishes. Some of these from the Ayrshire deposits are scarcely 

 larger than the Conodonts, but their appearance readily allows 

 them to be separated. 



I append short descriptions of the various forms, and refer to 

 the localities where those already described have been previously 

 found. To avoid repetition of the references, I may here men- 

 tion that the Russian Conodonts were described by Dr. Pander in 

 his " Monographie der fossilen Fische des Silurichen Systems 

 der Russischen — Baltischen Governments," St Petersburg, 1856. 

 The Conodonts from the Carboniferous of Ohio are described and 

 figured by Dr. Newberry in the 2nd volume of the " Palaeontology 

 of Ohio ; " and those from the Silurian and Devonian of North 

 America by myself in the Quarterly Journal of the Geological 

 Society for 1879. 



[For easy reference I may here give the stratigraphical position 

 of the various localities in which I have found Conodonts in the 

 Carboniferous limestone strata of the West of Scotland. 



Upper 

 Limestones. 



Stacklawhill, Stewarton. 

 Glencart, Dairy. 

 Monkcastle, Dairy. 

 Linn Spout, Dairy. 



Orchard, near Thornliebank. 

 Robroyston, near Glasgow. I Middle 



Limekilns, East Kilbride. | Limestones. 



Hillhead, Chryston. 



