118 ME. W. WICKHAM KING ON THE PEEMIAN [Feb. 1 899, 



At Handsworth railway-cutting, still farther north, the trappoid 

 zone is only 20 feet thick, and the materials are very fine. It is 

 overlain by Permian sandstones (D"). Therefore the coarse breccias 

 of Northfield also change gradually to breccia-sandstones and marls 

 in a northerly direction. 



VII. Conclusions based on the Yaeiation in the Coaeseness of 

 THE Materials. 



Having now completed the description of the changes in the 

 Middle and Upper Permian rocks, it remains to compare South-east 

 Shropshire and South Staffordshire, as follows : — 



(i) In both regions there is a middle series of calcareous zones 

 interstratified with sandstones and marls, preceded by chick 

 marls, and succeeded by breccias. This triple series suggests 

 the probability that the calcareous zones of the two regions 

 correspond in age. 



(ii) In both regions, A^ & B^ are chiefly marls in the southern 

 parts of the regions described, and sandstones in the northern. 



(iii) In South Staffordshire B' & C^ are coarsest and thickest in the 

 centre (from south to west). But in these central portions 

 they are most conglomeratic, thickest, and the pebbles largest 

 towards the E.S.E., a direction that differs but slightly 

 from the S.S.E. source indicated by the South-east Shropshire 

 region. The materials of tlie'Middle Permian in other areas 

 towards the north-west (Alberbury), however, may come from 

 a different direction. 



(iv) The trappoid breccias of both regions (a) are coarsest and 

 thickest at their southern extremities, and (6) show an 

 upward transition into marls. 



YIII. The Pebbles of the MinDLE Peemian Conglomeeates. 

 (Tables III & IV.) 



xit all the localities cited in the • foregoing pages, where the con- 

 glomerates of the Middle Permian occur in place in the calcareous 

 zones, I have made a careful examination of the pebbles in the 

 conglomerates, and have endeavoured to fix the geological horizon 

 of the rocks of which the several pebbles are composed. Many 

 of these fragments are fossiliferous, and their age can be estab- 

 lished with more or less approximation to certainty. Others are 

 unfbssiliferous, but the age of many, if not all, of these may be 

 determined by comparison with rock- types that occur in place and 

 the age of which is already known. 



The rocks so far found in these Middle Permian calcareous 

 zones are as follows : — 



(1) Aech^an. These comprise the following : — 



Finely laminated hornstones, or halleflintas (green, 



