TBANSAOTIONS OF THE SECTIONS. 09 



Orthis calligramma, ^ 

 — — elegantula, var. a. 



parva, t exclusively Cambrian. 



Leptmna sericea, 



quinguecostata, J 



Spirigerina reticularis, Cambrian to Devonian inclusive. 

 In a second excavation, 30 yards higher up the river, occurs a bed with innume- 

 rable specimens of Trinucleus. Still further up the river, the well-known Caradoc 

 beds of Horderley. 



In this section, therefore, the highest beds are undoubted Wenlock shale, the 

 lowest are undoubted Cambrian (Caradoc sandstone of the Bala group), and the in- 

 termediate May Hill group is lost. These facts do not invalidate, but, so far as they 

 go, confirm the conclusion drawn from the Norbury section ; and tend to prove that 

 the author was in error, when, in a previous communication, he placed the Penta- 

 merus beds within the limits of the Caradoc group (paper read before the Geol. Soc, 

 Nov. 3, 1852). 



(3.) Sections of Shineton, 8fc., where the terrace of Caradoc Sandstone approaches the 

 right bank of the Severn (Map of the' Silurian' System). — As the author was pre- 

 vented from examining these sections, he gives verbatim the notes upon them by 

 Professor M'Coy: — 



" (1.) Close to Shineton Church, olive shales on the roadside j dip about 35° E. 

 of S. at about 30°, containing — 



Agnostus pisiformis (as at Llandeilo, &c.), in gr at abundance ^ 



Olenusi Isame as at Hollybush) (PhiUips' Malvern Section, see his Memoir, 



p. 55.) 

 Asaphus ?, undetermined fragments. 



Cytheropsis Aldensis (as at Aldens on the Stincher, N.B.). 

 Siphonotreta micula (as at Wellfield, Builth, and at Pentre, N. of Llangynyw). 

 " All the above are Cambrian types. 



" (2.) Over the above, and also over some black shales with a few traces of JFlwct 

 and Orthoceratiies, in Belswardine Brook, several thin beds of Pentamerus limestone 

 and May Hill sandstone occur (dip about 50° E. of S. at 20''), full of — 

 Hemithyris hemisphcerica. 

 Pentamerus lievis. 



oblongus. 



Petraia (unnamed species, same as at May Hill and Malvern). 

 " (3.) One mile W. of Harley, olive-coloured shales like those at Shineton, with 

 nearly the same dip and direction, are overlaid (with a small unconformity) by very 

 coarse unfossiliferous May Hill conglomerates (exactly like those forming the base 

 of the May Hill sandstone near the top of May Hill), seen in numerous openings 

 extending along the road to Church Preen. 



"Beneath the above conglomerates, in the large quarries at W. edge of Round Nursety 

 near Harnage Grange, the Caradoc sandstone and limestone are found, both dipping 

 10° E. of S. at about 20°, and full of .the following fossils : — 



Orthis expansa, ^ 



all exclusively Cambrian." 



J 



These sections (at Shineton, &c.) had been previously examined, in detail, by 

 Mr. Salter, whose list of fossil localities w,as kindly communicated to Professor 

 M'Coy and the author before their visit to the country. 



The conclusion from the above facts seems to be inevitable. The great (and sup- 

 posed) typical section of Caer Caradoc and Wenlock Edge is not, probably, a con- 

 tinuous, but a broken section ; and the conglomerates, grits, Pentamerus limestone, 

 &c. (which overlie the Olenus shales) must here (as at the Malverns) be cut off from 

 the Caradoc terrace, and arranged with the Wenlock group, as in the above first ta- 

 bular view. 



From all the above facts, as well as from facts previously published, the author 



