634 EDWARD HULL ON THE CLASSIFICATION 



Stage E. Gannister Beds. — Shales &c. with the " Slaty-band " ironstone with 

 marine shells ; Lingula mytiloides, Discina nitida, Axinus deltoidcs, Mur- 

 chisonia, Conularia quadrisulcata, Nautilus*. 



Stage D. 340 to 400 feet. — " Moorstone-Rock " series (Roslin sandstones) with 

 accompanying beds down to the Garnkirk Limestone. Fossils marine. 



Stage C (?). Yore-dale Beds.—(b) " Upper Limestone Series" of Scottish geo- 

 logists, including the Garnkirk-limestone. 

 (Marine and Estuarine beds.) 290 feet 

 thick. 

 (a) " Lower Coal and Ironstone Series." Shales, 

 coals, and black-band ironstones with fish, 

 Entomostraca (Carbonid), &c. (Estuarine 

 and freshwater.) 160 feet. 



Stage B. — "Lower Limestone Series," including the Roman Camp and Gil- 

 inerton Limestones (marine), 522 feet. 



Stage A. — " Calciferous Sandstone Series " in two groups, the upper (b) variable 

 in thickness and extent, consisting of white and grey sandstones, bitumi- 

 nous shales and limestones with cyprids, fish, &c. (Burdie-house limestone 

 near Edinburgh) ; the lower (a) of dull reddish sandstones, shales, conglo- 

 merates, and beds of " Cornstone " (Plants &c). 



Mr. J. Young, of the Himterian Museum, is of opinion that the 

 lower division of Stage C is of freshwater origin. Marine shells are 

 absent, while Entomostraca of the genus Garbonia are abundant in 

 the shales ; of these, ten species have been determined by Messrs. 

 Rupert Jones and Kirkby. 



In the above section of the Scottish strata it will be observed that 

 I have ventured to insert two groups not hitherto recognized — ■ 

 namely, Stages E and C, representing the " Gannister Beds " and 

 " Yoredale Series " of England respectively. I have never been 

 able clearly to understand why these two groups have failed to be 

 admitted into the classification of the North- British Carboniferous 

 series, as it was difficult to conceive that groups which in North 

 Lancashire and Yorkshire attain considerable proportions (about 

 2000 and 3000 feet respectively) should have altogether thinned 

 away, or disappeared north of the Border Land. 



During the debate, however, which took place upon the reading 

 of my paper at Glasgow, Mr. John Young, F.G.S., suggested that if 

 representatives of the Gannister-beds were to be found in Scotland at 

 all, it would be in the horizon of " the Slaty black-band ironstone " 

 series, which is rich in marine forms, and lies immediately above 

 the "Millstone-Grit series." The fossils which are above enumerated 

 have been collected by Dr. W« Grossart, in the parish of Shotts : and 



* Determined by Dr. W. Grossart, and communicated to the author by Mr. 

 John Young, F.G.S., of the Himterian Museum, Glasgow. 



The following are the fossil forms from the Slaty -band Ironstone given in the 

 Memoirs of the Geol. Survey of Scotland from Lanarkshire — Lingula myti- 

 loides, L. squamiformis, Anthracosia subconstricta, A. acuta, A. aquilina. (Ex- 

 planation of Sheet 23, p. 89-90.) 



Those from the Millstone Grit are — Lingula mytiloides, L. squamiformis, 

 Orf.his resupmata, Streptorhynchus crenistria, Naticopsis, sp. inc. (Ibid. p. 89.) 



