278 PROFS. LLOYD MORGAN AIsTD REYNOLDS ON THE [Aug. I9OI, 



comparative worthlessness for road-me tailing, is much shattered 

 and disturbed, shows plentiful veining and many slickensided faces, 

 and is in places full of small fragments, about ^-inch or less in 

 diameter, of baked shale, so that at times it takes on an appear- 

 ance not very dissimilar to a fragmental deposit. The most com- 

 pact and freshest -looking rock in this quarry is in the south-western 

 portion, where it contains plainlj'- visible grains of clear quartz. 



Along the north-western edge of the quarry are several exposures 

 of sedimentary beds overlying the trap and lying on a roll of its 

 irregular surface. These were noted by Weaver,^ in whose time 

 they were probably fresher and less overgrown than they now are. 

 By removal of the soil, however, sufficient can even now be seen to 

 throw light on the nature and origin of the rocks. In the most 

 easterly exposure there lies upon the trap about 4 feet of sandy and 

 ashy limestone dipping north-westward at 45*^ to 50°. Fossils are 

 distributed throughout, and undoubted lapilli are plentiful in the top 

 band and in the bottom 6 inches. These are well seen both in 

 hand-specimens and in microscopic sections, and indicate in the most 

 unmistakable manner the occurrence of contemporaneous volcanic 

 activity. This section alone shows that here on the lower trap- 

 horizon, as at Charfield Green on the upper horizon, whatever be 

 the nature of the trap itself, there are contemporaneous volcanic 

 ashes. And their relation to the trap, together with its highly 

 vesicular character, strongly suggests, if it does not prove, that the 

 trap itself is a contemporaneous lava. 



In the ashy limestone Mr. Eeed identified the following fossils : — 



Cheirurus sp. 



Pleurotomaria sp. 



Orthis ealligramma, Dalm. 



0. rustica, Sow. 



0. jyoly gramma, Sow. 



Atrypa imbricata (?) Sow. 



Strlcklandinia lirata, Sow. 



LeptcBna rhomboidalis, Wilck. 



Fentamenis imdatus (1) Sow. 



Favosites gothlandica, Fougt, 



F. Forbesi, M.-Edw. 



F. Bowerhanki (1) M.-Edw. & Haime. 



Lindstrcemia bina, Lonsd. 



Tliis assemblage of fossils shows that the beds are of Upper 

 Llandovery age. There is a well-marked coral-band resting 

 immediately upon the trap. 



The only other trap-exposure lies farther south-west on the same 

 line of strike, under the hedge on the left bank of the stream which 

 joins the Little Avon at Middle Mill. The rocks here do not call for 

 detailed notice. Above and below are mere compact bat somewhat 

 vesicular bands, and between them, as in the old quarry, are more 

 irregular and shattered bands, with abundant small amygdules, and 

 containing minute fragments of baked shale, often very rotten and 

 showing spheroidal weathering. 



The trap-band is not traceable farther to the south-west, no 

 exposures of rock in situ being visible. 



^ Trans. Geol. See. ser. 2, toI. i, pt. ii (1819) pp. 330-31. 



