1849.] THOMSON ON THE POSITION OF SHELLS IN THE CRAG. 353 



Pits of Red Crag. 



Cliillesford, — by the side of the road from Orford to Woodbridge, at 

 the point where the lane (east side of it) branches off to Chillesford 

 church : a fine large section*. 



Ditto : — several small pits on the heath, about half a mile north-east 

 from Chillesford brick-kiln. 



Tits of Fossiliferous Clays and Sands {b & c) overlying the Coral- 

 line and Red Crags. 



Iken parish : — brick-field. (See page 347.) 



Ditto : — two small pits at the back of the keeper's house, seven fur- 

 longs west of the last pit. 



Ditto, — on the edge of the wood, three furlongs south-south-west of 

 the last pit. [In the last two pits the red crag occurs at their 

 base ; fossils scanty.] 



Chillesford : — pit by the church, described at p. 348. 



Ditto : — at brick-kiln, described at p. 347. 



Ditto : — on the Tunstall-road, quarter of a mile from its junction with 

 the Orford and Woodbridge roads. 



Pits in Clays '' b & c"; in places fossiliferous. 



Iken parish : — pit described in page 346. 



Ditto : — an old pit in a field quarter of a mile south-east from Yarn 



Hill. 

 Tunstall parish : — on the south side of the road leading from Tunstall 



to Iken Heath, one mile and three furlongs nearly due west of 



Tunstall church. 

 Ditto : — in a field quarter of a mile south of the same road, half a mile 



nearer Iken Heath f. 



2. On the Position i?i which Shells are found in the Red Crag. 

 By T. G. Ringler-Thomson, Esq. 



[Communicated by Professor Ansted.] 

 \_Abst?'act.^ 

 The unvarying position of the bivalve and univalve shells in the red 

 crag formation of Suffolk and Essex, in many localities, has not, that 

 I am aware of, been ever publicly discussed. The inexhaustible 

 stores of Pectunculi in this formation, as well as the other less nu- 

 merous bivalves, are deposited m layers of various thickness, from 

 six inches to as many or more feet, each shell having its inside or 

 concavity downwards, and the umbones of the shells having in general 

 an easterly direction. 



* On the opposite side of the Butley river, in the parish of Butley, are several 

 good pits of red crag. I would especially notice those about half a mile westward 

 from the Old Abbey. 



t The greater number of the numerous clay- and sand-pits in the parishes of 

 Tunstall, Wantesden and Iken, are in the unproductive sands overlying the crag 

 and in the great northern clay-drift. Around Orford are many of the former. 



