﻿54 



PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Dec. 4, 



gether evident. We find amongst none of the beds any traces of 

 fossils to which can be referred the thick deposit of anthracite — no 

 fucoids, nor any remains of vegetables of any description ; and yet 

 there can be little doubt that this substance is the result of some 

 kind of vegetation which flourished during the epoch of the Caradoc 

 sandstone. 



Sir Roderick Murchison refers the anthracite schists of Scandinavia 

 to large forests of algae and fuci which originally existed in the Si- 

 lurian seas of that region, and which have, " from their ready decom- 

 position and the great changes which the sediments have undergone," 

 lost all traces of their original forms. The large portion of carbon 

 which is found in the dark shales above the anthracite, and to which 

 they owe their colour, seems to corroborate the opinion as to the 

 readiness with which fucoids may have been decomposed. Prof. 

 Nicol has also found small fragments of this substance amongst the 

 Grieston slates on which " some markings occur which may have 

 been algce" '; but, from the ashes of the anthracite, he is disposed to 

 refer the plants which have constituted it, to a higher class of vege- 

 tation than fucoids. Whatever may have been the origin of this 

 anthracite, there can be no doubt that the deposits which imme- 

 diately succeeded it had in the first instance the nature of black mud, 

 and that this mud owed its composition in part to an addition of the 

 remains of decomposed organisms. Such a muddy matrix doubtless 

 afforded a suitable habitat for the Graptolites, the remains of which 

 are now so plentifully entombed in it, and which, from the decompo- 

 sition of the iron pyrites, into which they were converted, are now 

 furnishing the chalybeate and saline-sulphureous springs of the 

 county with their medicinal properties. 



Silurian Fossils of Kirkcudbrightshire and the position in which 

 they occur at the eastern entrance of Kirkcudbright Bay. 



Some time ago Lord Selkirk presented the Geological Society with 

 a suite of fossils which had been collected by Mr. Fleming, of the 

 Kirkcudbright Academy, on the east side of the bay of Kirkcudbright, 

 and these fossils were named by the Geological Survey.^ 



The locality at which these fossils occur is called Balmae, and is 

 at the point which marks the eastern termination of the bay. Here 

 the remains are found in three different spots. The one furthest to 

 the east, near the headland called Howell Point, affords a dark- 

 coloured greywacke flagstone, in which one species of Graptolite is 

 found in great profusion, to the exclusion of any other species ; this 

 appears to be the G. Ludensis, Murch. Amongst these, Orthocerata 

 also are met with in considerable quantities, the species consisting of 

 O. Sedgwickii, Forbes, 0. annulatum, Sow., and O. tenuicinctum ) 

 Portlock. These are the only fossils which occur at this spot ; the 

 beds which lie above and below the fossiliferous strata consisting of 

 the usual fine-grained greywacke sandstone. 



A short distance to the westward of this, at a point called Gipsy 

 Head, other fossils are to be found in strata which differ very mate- 



