488 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 20, 



during the period of the deposition of the limestone-shale, as well as 

 the uppermost beds of the Devonian series. 



These grits, we observed, differed little from the Devonian grits 

 below them, except in being chiefly grey, and having intercalated 

 beds of dark grey, instead of greenish, shales. The partings of black 

 or dark-grey shale constitute the only mineral character we could 

 find to separate the two series. 



The fossils of the Carboniferous Slates and Coomhola Series are 

 as follows : — 



Carboniferous Slate. 



Among a host of others occur Fenestella plebeia, Actinocrinus, Platy- 

 crinus, Poteriocrinus, and Rhodocrinus, which I think identical 

 with the Carboniferous forms. With them, however, were in 

 abundance Spirifer cuspidatus, a Carboniferous form, with S. 

 disjunctus ? (I believe this to be the wide form of S. bisulcatus, 

 so common in all the Pembroke sections). In addition were 

 Orihis Michelini, Streptorhynchus crenistria, Athyris squamosa, 

 Productus, sp., Rhynchonella pleurodon (abundant), Orthoceras, 

 Nucula, and, lastly, the Modiola Macadami, Portlock, — a shell 

 abundant in Lower Carboniferous beds. Annelide- trails and 

 -burrows were abundant in all the beds, as they are also in the 

 underlying Coomhola Grits. 



Coomhola Series. 

 In the western part of Cork, and notably at Dunworley Bay, Dirk 

 Bay, Skibbereen, and Glengariff, we have Encrinites of the same 

 genera as above, but several of them apparently of different 

 species from those of the Carboniferous Limestone. Rhyncho- 

 nella pleurodon, Spirifer cuspidatus? (doubtful), S. disjunctus 

 (S. Verneuilii, Murch.); many undescribed bivalves of the genera 

 Modiola, Ctenodonta (Nucula), Cucullaia, Axinus, Avicula, Avi- 

 culopecten, and a new genus for which I proposed the name 

 ~ Curtonotus; Bellerophon, with rounded, keeled, and trilobate 

 dorsal edges, as in North Devon ; Cucidlosa of several species, 

 and C. trapezium ; Lingula, new large species ; Rhynchonella 

 pleurodon and R. laticosta? ; and, lastly, the most common 

 Shell and Plant, Avicula Damnoniensis and Knorria dichotoma 

 in every shale-bed. 



The conclusions we arrived at were : — 



1. That in South Ireland the Yellow Sandstone was the upper 

 part of the Old Bed. 



2. The Carboniferous Slate, whether well or thinly developed, 

 contains in its upper part the ordinary Carboniferous types. 



3. A local but considerable group intervenes, physically more con- 

 nected with the Carboniferous, but distinct as to fossils. It has the 

 same Plants as the Upper Devonian (that is, Upper Old Bed), some few 

 Shells of the Carboniferous Limestone, and numerous Bivalves pecu- 

 liar to itself. This group is the equivalent of the Marwood sandstones*. 



* In part only : as I have above shown (p. 480), it is the true equivalent of the 

 Upper Pilton group. — J. W. S. 



