446 Dr. Wheelton Hind S( John T. Stohhs— 



the Gwespyr Sanilstone, whose representative is exposed in a quarry 

 near Berwig Station. The beils here resemble closel}', both in 

 <5olonr and in petrohigioal character, the sandstones and grits of 

 Gwespyr, and contain many fragments of phmts and woody debris. 

 At the top of the hill at Pen-y-Bwlch are a series of strong cherts, 

 whit'h crop out behind the houses in the village. Morton mentions' 

 that the sandy limestones and white sandstones with quartz pebbles, 

 about 170 feet thick, are to be seen at Craig Mawrand Craig Fechan. 

 At IMinera tlie limestones rest directly on the Bala Beds, with a thin, 

 patchy basement conglomerate, and the junction can be seen and 

 tracetl for some distance in the bed of the stream which runs from 

 Ty hir through the quarries called the Clywedog. The lower beds 

 of limestone are crammed full of Davicsiella LlnngoUcnsts (Dav.), a 

 very easily recognised species, even in section, on account of the 

 large comparative thickness of the pedicle valve. This species we 

 consider to have a time value in North Wales, a fact which Morton 

 seems to have recognised, for it alwaj's occurs in his lists of fossils 

 from the Lower Brown Limestone. In the case of IMinera, however, 

 ]\lorton did not recognise the existence of the Lower Brown Lime- 

 stone, but refers the lower beds (IGO feet) to his Upper Wliite 

 Limestone division. From a colour point of view he is certainly 

 correct, since there is no hnnrn limestone in this locality, but the 

 presence of large numbers of D. Lhxmjolleiisis — evidently the maximum 

 of this fossil — seems to ns to be conclusive evidence of the contem- 

 poraneity of these bods with otliers containing the same fossil. 

 Beds immediately above the Daviesiclla beds contain abundance of 

 Sf))ii')inla aflf. firoith's, giving a similar paU\3ontological succession to 

 that at Llandulas. 



Morton estimates the whole limestone series at Minera as 436 feet 

 thick, and D. LhtugoJlensis is confined to the lowest few feet of the 

 series. Fossils were very rare indeed in the succeeding 350 feet 

 of limestone. Quarrymen said that specimens occurred only 

 occasionally, and we were not able to fnid any in the loose blocks 

 about the quarry. 



On the other hand, the upper beds of limestone east of the large 

 quarries, exposed successively in abandoned quarries and outcrops 

 on the hill, contain the typical fossils of that zone, viz. : — 



Cyathophiilhiin ct'. reijiiim, Phill. Loifdalfia rugo.ta, WQo^. 



lithostrodon irirtjuhtre (rhill.). JVodiicfus (/i(/(intt-us (Mart.). 



Z.JuHciiim (Flom.). Ami mauy beds ot'criuoids. 

 L. Fortlocki (Biomi). 



In this series the limestones become cherty, and the beds assume the 

 lithological character of the upper limestones on llalkj'n IMountaiu. 

 Morton gives a much longer list of fossils from the Upper Grey 

 Limestone of Minera than we collected — a list which we are pre- 

 pared to accept, with three exceptions, because we know the species 

 enumerated occur universally at this horizon in the counties of 

 Flint and Denbigh. The exceptions are — (1) Athyris lioijssii, which 

 should probably stand (or A. planostdcata, Phill.; (2) AvicHlo})ecten 

 1 Op. sup. cit., p. 71. 



