W. Keeping — Geology of Cardigan Toion. 519 



II. — On the Carboniferous Limestone of the Western Sahara. 

 By Dr. G. Stache. Proceedings of the Imper. Acad., Vienna, 

 June 22, 1882. 



N his journey from Morocco to Timbuctoo, Dr. 0. Lenz collected 

 many fossils characteristic of the Carboniferous Limestones. 

 Four groups are distinguishable, namely — 1. Productus-limestone of 

 Fum-el-Kossan in the northern region of the West Sahara, and the 

 calcareous zone of Wady-Draa. 2. The Spirifers in the sandstones 

 of the middle region. 3. Corals and Crinoids at several localities 

 along the Western Srony Desert. 4. Fossils in the marls and lime- 

 stones with Crinoids at Igidi in the south part of the Carboniferous- 

 limestone region. 



These groups represent portions of a great Carboniferous-lime- 

 stone fauna ; and the lower unproductive subdivision of the Carbon- 

 iferous system is by far the most extensive series of strata in the 

 wide north region of depression in the Western Sahara. The Pro- 

 ductus-limestone of the northern zone, and the Crinoidal marls with 

 Productus of the southern zone, belong to a series corresponding 

 with Gosselet's " Etage du Calcaire de Tournay," or the lower sub- 

 division of the Carboniferous Limestone of Belgium. The Lower 

 Carboniferous strata in the middle and eastern portion of the great 

 area of dej^ression in the North Sahara may possibly be of more 

 importance than hitherto supposed. 



It is probable that during the early part of the Carboniferous 

 Period the sea limited the Mid-African Continent along an extensive 

 East and West coast-line ; and that during the same period there 

 was an open communication between the North-African sea and 

 that which was inhabited by the faunae of the Belgian and South 

 Alpine Carboniferous Limestones, both abounding in Productus. 



Count M. 



laEiFOiEaTS .A.ITX) :Pi2,ooEEiDiiNrc3-s. 



British Association, Southampton, August, 1882. 

 I. — The Geology of Cardigan Town. By Walter Keeping, 

 M.A., F.G.S., Keeper of the York Museum. (Bead before Section C) 



A FEW years ago, in the course of a geological investigation in 

 South Wales searching for the base-line of the Llandovery 

 group of rocks, I came to the town of Cardigan. 



Now, seeing upon the Geological Survey Map the tract of country 

 between Cardigan, Newport, and Dinas Head, in Pembrokeshire, 

 marked, like the Aberystwyth Grits, * b. 4,' i.e. Lower Llandovery. I 

 came here in the full expectation of finding the rocks of the same 

 Llandovery age. 



But the first glance at the cliffs in Newport Bay showed that this 

 was most unlikely to be the case ; for the grit beds here are of quite 

 a different type from those of Aberystwyth, namely, pale blue and 

 grey felspathic grits, much less quartzose, and very ash-like in 



