On the Torridon Sandstone. 143 



fossils had been collected from or referred to the Blackdown beds, 

 and a sketch of the literature of the subject, passed on to a correlation 

 of the Blackdown beds with deposits in other localities. He pointed 

 out that they do not contain a sufficient number of species in common 

 with the Marne de Bracquegnies to justify an identification with 

 this. He compared them with the Haldon beds, and, by a com- 

 parison of the fossils bed by bed, showed that of 196 Blackdown 

 species (omitting a few corals) 50 occur at Haldon : the latter 

 section, however, represents not the whole, but only the upper part 

 of the former, nine beds in the lower part of it being without 

 representatives at Haldon. Here also the higher beds contain a 

 thin band distinguished by a distinct and all but unique fauna (the 

 zone containing the corals described by Prof. Duncan). Comparing 

 the Blackdown beds with lists of Cretaceous fossils from other 

 localities, it would appear that we have neither exclusively Lpper- 

 Greensand forms at the top, nor exclusively Lower- Greensand 

 forms at the bottom, nor exclusively Gault forms in the middle. 



2. •• On some new or little-known Jurassic Crinoids." By P. 

 Herbert Carpenter, Esq., ALA.. 



3. " Xotes on the Polyzoa of the ^Venloek Shales, Yv"enlock Lime- 

 stone, and Shales over the "Wenlock Limestone. From material 

 supplied by G. Maw, Esq., E.L.S.. F.CMS* By ft B. Tine, Esq. 



December 21. — Eobert Etheridge, Esq., E.B.S., President, 

 in the Chair. 

 The following communications were read : — 



1. " The Torridon Sandstone in relation to the Ordovician Bocks 

 of the Northern Highlands." Bv C. Callawav. Esq., M.A.. D.Sc. 

 F.G.S. 



The author pointed out that the apparent difference in dip 

 between the Torridon sandstone and the overlying quartzite in the 

 neighbourhood of Loch Broom was due to some markings in the 

 former which suggested a direction of bedding which was not the 

 real one, and that the one rock passed gradually into the other. 

 The two are perfectly conformable at Strath AuchalL where the 

 junction can be well studied, also between Lnaport and Strath 

 Kennort, on the north side of Loch Assynt and south of Lnaport. 

 The author then considers that there is proof of the conformity of 

 the quartzites with the Torridon sandstone, and that there is no 

 unconformity as generaUy suggested. In this case it appears to 

 him to follow that the Torridon sandstone must be either Ordovician 

 or Lpper Cambrian in age, and that the former is more probable, as 

 the overlying quartzite is not more than some 500 feet thick, so that 

 the united thickness of the two hardly exceeds at most that of the 

 Arenigs of Shropshire or South "Wales. 



2. " The Precambian (Archfean) Bocks of Shropshire." Part II. 

 By C. Callaway, Esq.. D.Sc, E.G.S. 



The author described the western axis of Archaean rocks in 



