Vol. 63.] OF THE BATH-DOULTING DISTRICT. 409 



late Edward Wilson, the Upper Trigonia-Gvit has diminished con- 

 siderably in thickness : at the place where they observed the details 

 recorded in their section it measured only 6 inches. 1 



Now, near the beginning of this paper (p. 385) it was remarked 

 that, when the Upper Trigonia-Grit was followed from north to 

 south, from Bath towards the Mendips, it was seen to transgress the 

 outcrop-edges, as a general rule, of successively-older deposits. In 

 the Lyncombe cutting, the bed which contained specimens of Hildo- 

 ceras bifrons and species of Dactyl ioceras occurred beneath at least 

 100 feet of Midford Sands. Then came the Upper Trigonia-Grit. 

 But in the cuttings near Wellow, Buckman & Wilson found the 

 *■ grit ' resting directly upon portions of the Cephalopod-Bed ; no 

 Sands intervened. The sections in the cuttings, so far as the Lias 

 is concerned, are now overgrown ; but in the roadside near the 

 railway-bridge at Wellow there is this succession : — 



(<?) Section in the Lane at Wellow, near Eadstock. 



Thickness in feet inches. 



m-p. a o, 1 Limestone, massive, with an occasional 



. DOULTING STONE. > , , •' in 



, 9 . j beleumite 1 < 



/Limestone, sandy and ferruginous at the 



VI. Upper Trigoxia- I bottom, containing a lew small iron- 



Grit. ] stained derived fragments (at the 



^ base) 1 8 



- - - - (Non-sequence.) 



Bifrontis Limestone, hard, pale-brown and bluish- 

 grey, ironsbot; Belemnites spp., Hil- 

 doceras bifrons (Sowerby), Baciylio- 

 ceras cf. Braunianum (d'Orb.), and 

 Bhynchonella aff. jurensis, Dav., non 



Quenstedt, to which are joined 11 



Falciferi (?) Irregular masses of yellowish limestone, 



with numerous belemnites 8 



Clay, very fine-textured, somewhat mica- 

 ceous. 



Beds III and VI in particular are much disturbed, and III may 

 have been superimposed on VI by slipping, and may really be portions 

 of the same bed. This seems probable, because the Coral-Bed is well 

 developed at Midford, and near Woodbarrow Farm on the opposite 

 side of the valley to Writhlington, and its absence from the inter- 

 mediate locality is scarcely to be expected. 



Crossing the River Somer at Wellow, the Upper Trigonia-Grit is 

 seen near the spring at the junction of the Faulk! and and Norton- 

 St. Philip Lane. Here it is a veritable Conglomerate-Bed, containing 

 rolled and frequently bored (by Lithophagi) pebbles of a bluish- 

 grey fine-grained sandstone and of a dense oolitic limonite. The 

 fossils recorded are Ctenostreon pectiniforme, Ostrea (large species), 

 Isastrcea (fragment), Lima (Limatida) gibbosa, Trigonia costata, 



1 Quart. Journ. Geol. Soc. vol. lii (1896) pp. 711-12. 



