138 
THE CRETACEOUS ROCKS OF BRITAIN 
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The remarkable phenomenon was first noticed by Mr. Whitaker 
in 1871, but has not been described by any subsequent writer. 
The actual facts are rather more complicated than is represented 
in the diagram given by Mr. Whitaker, and it will be more con¬ 
venient to discuss them when describing the Middle Chalk (see 
Fig. 77, p. 439). In this place it need only be said that the disap¬ 
pearance of the beds above mentioned, together with the greater 
part of Bed A, can be ascertained by a careful examination of the 
large fallen blocks on the undercliff near the boundary line between 
the parishes of Beer and Branscombe. 
There are three of these blocks near the outer footpath, and the 
two more easterly both show about two feet of coarse fossiliferous 
grit, in every respect similar to the basal part of A at Beer Head ; 
this grit yields the same Bryozoa and Sponges, and rests on a well 
marked surface of a massive calcareous sandstone, suoh as 
forms everywhere the top of the Upper Greensand. 
The third block, which is known as Mitchell’s Bock, has come to 
rest in a more horizontal position, and includes a fair thickness of 
the overlying chalk. This block shows 3 feet of bed A, with the 
same characters and many fossils, especially in the upper foot, 
which is immediately overlain by the soft white chalk of the Tere- 
bratulina zone. From the fossiliferous grit in this block I obtained 
the following fossils * : — 
Elasmostoma sp. 
Tremacystia d’Orbignyi. 
Membranipora sp. 
Ceriocava ramulosa. 
Badiopora (Cellulipora) ornata 
Rhynchonella dimidiata. 
Pecten acutus ? 
„ hispidus. 
Lima sp. 
Modiola sp. (cast). 
Pectunculus sp. 
Trigonia vicaryana. 
The west end of these cliffs is inaccessible, but, so far as can be 
judged by looking from the top, the conditions existing at Mitchell’s 
Rock continue to the mouth of the Branscombe valley. There is, 
however, a small quarry about half a mile east of Branscombe 
Vicarage, where A appears to be absent, while a thin representative 
of B is present, the section being as follows : — 
ft. 
Soil, with flints --------- 2 
Yellowish loam, with scattered flints and remnants of soft 
chalk at the base ----.----3 
Very hard compact white limestone without glauconite - \ 
Hard glauconitic limestone, with green-coated nodules and 
many fossils, Am. [. Acanth .] Mantelli , etc. - - - - l 
Hard calcareous sandstone, rough, and full of quartz for about 
3 feet, passing down into massive sandstone, which has been 
quarried for building stone (Selbornian), seen for - - 12 
The-beds dip eastward at about 3°, and a fallen block exposed the 
plane of separation between the sandstone and the limestone, show¬ 
ing a layer containing many pebbles of sandstone and many speci¬ 
mens of Trigonia (chiefly T. excentrica ) and some other fossils. 
This layer is merely the thickness of the pebbles and fossils, and is 
all that can be regarded as representing the Bed A. 
* The Sponges and Bryozoa were kindly identified by Ur. Hinde. 
