of the Vale of Wardour. 2h1l 



is a mattei' of opinion, and I can understand that as he and 

 Mr. Woodward were obliged to draw a line somewhere for de- 

 lineation on the map of the Geological Survey they gave the Wealden 

 the benefit of the doubt. 



Mr. Andrews and I considered these beds as a continuation of the 

 Upper Purbeck, and we obtained fossils from the material thrown 

 out of a well sunk at the cottages near Dinton Station ; it is true 

 that most of the species found range from Purbeck to Wealden, but 

 they included Cypridea punctata, which has not yet been recorded 

 from Wealden. The well is 40 feet deep, and the fossils probably 

 came from less than 30 feet down. How much of this thickness 

 is Purbeck and how much Wealden is evidently a matter of opinion 

 and extremely uncertain. The following may be given as a summary 

 of the beds which lie between the Lower Greensand and the Middle 

 Purbeck, near Dinton, with estimated thicknesses : — 



feet. 

 4. Yellow and grey silty clays by Dallwood Farm ... 15-20 



3. Grey silty marl (in the well) 10-12 



2. Stiff grey and yellow clays (in the well and cutting) ... 25 



1. Marls, shales, and grits (in the cutting) 12 



No. 1 is Upper Purbeck ; No. 2 may be either Purbeck or Wealden ; 

 Nos. 3 and 4 are probably Wealden. 



4. Purheck and Wealden at Teffont. — When in 1890 Mr. Andrews 

 and I endeavoured to trace the Upper Purbeck and Wealden clays 

 towards Teffont we found that their thickness became very much 

 less, and that the space occupied by their outcrop north of Teffont 

 Kectory was very narrow. We found there exposures of the following 

 beds in descending order : — 



D. Black clay. 



C. Greenish -black glaucouitic sand. 



B. Mottled clay, white, yellow, and claret -coloured, like the ' cat's-brain' 



clay of Kentish Wealden. 

 A. Yellow silty clays. 



The upper two members of this succession we regarded as Lower 

 Greensand (Vectian), the lower two as Wealden, believing A to be 

 part of the Dallwood Farm beds, No. 4 of the series near Dinton. 

 We saw nothing between this and the Middle Purbecks, and there 

 did not seem room for the Upper Purbecks (Nos. 1 and 2) to come 

 in, so that we concluded the Wealden had here overlapped the 

 Upper Purbeck Beds. 



From the newly issued 1 inch map I find that Mr. Reid does not 

 carry the Wealden clays so far west as the point where we saw the 

 above succession, but has coloured all the beds north of the Rectory 

 between the Middle Purbeck and the Vectian Sands as Upper 

 Purbeck. It is clear, therefore, that Mr. Reid agrees with us in 

 thinking there is not room enough here for the whole thickness of 

 Upper Purbeck and Wealden, but differs from us in regarding the 

 beds which do occur as Purbeck instead of Wealden. In the 

 explanation of the map (Sheet 298) he does not describe any 

 exposure of these beds north of Teffont, either under the head of 

 Purbeck or Wealden, but quotes our description of them in his 



DECADE IT. VOL. X. NO. VI. 17 



