312 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [April 9, 



which caps the hill, consists of a light-brown oolitic limestone, 

 speckled Tvith an abundance of dark, flattened, glistening grains of 

 hydrate of iron ; in some beds the oolitic grains are very large, and 

 almost pass into a pisolite. A few years ago, when this rock was 

 worked, a great many fossils were obtained from it. My kind friend 

 Dr. Symes, of Bridport, who at that time collected the fossils obtained 

 from Chideock, gave me fine specimens of the following species : — 



Cephalopoda. 



Ammonites Martinsii, d'Orb. Ammonites subradiatus. Sow. 



Gasteropoda. 



Pleurotomaria Proteus, Deslong. Pleurotomaria punctata. Sow. 

 elongata. Sow. ornata. Sow. 



Conchifera. 



Trigonia costata. Sow. Astarte trigonalis, Sow,, sp. 



Astarte modiolaris, Desh. Myoconcha crassa. Sow. 



Brachiopoda. 



Terebratula sphaeroidalis. Sow. Rhynchonella plicatella. Sow. 

 perovalis. Sow. senticosa. Von Buck. 



Echinodermata . 



Clypeus Agassizii, Wright. Colly rites bicordatus, Desor. 



altus, M'Coy. Hemicidaris Bouchardii, Wright. 



Collyrites ringens, Agass. Echinus bigranularis, Lamk. 



Anthozoa. 

 Montlivaltia trochoides, Edw. 8f Haime. 



Beneath the Inferior Oolite, there is a bed composed almost 

 entirely of the fragments of Pentacrinites^ and underlying this is the 

 Cephalopoda-bed, with Ammonites Dorsetensis, Wright, Ammonites 

 hircinus, Schloth., Gervillia Hartmanni, Miinst., Cucullcea, Modiola, 

 and large Limce. As the Inferior Oolite beds were those chiefly 

 worked, it was from that rock the fossils for the most part were ob- 

 tained. The Cephalopoda-bed consists of a fine yellow micaceous 

 sand, indurated in parts, and passing downwards into the loose sands 

 of the Upper Lias. The same bed is exposed in two or three road- 

 side quarries between Bridport and Chilcombe Hill, from which I 

 collected many good specimens o{ Ammonites Dorsetensis, Wright, 

 and where I saw many large Nautili and Belemnites in situ. The 

 rock consisted of a coarse, brown, rubbly oolite, traversed by sandy 

 seams, and was worked for road-mending. 



Oolitic character of the Cephalopoda-bed. — From the facts above 

 recorded, it is clear that the Cephalopoda-bed forms an important 

 and well-marked feature in the lower division of the Oolitic group : 

 although it contains sparingly a few species of Conchifera, such as — 



Pholadomya fidicula, Soiv. Modiola plicata. Sow. 



Gervillia Hartmauni, Miinst. Astarte exeavata, Sow. 



Myacites abductus, Phil. Hinnites abjectus, Phil. 



Pecten demissus, Phil. Pema rugosa, Gold/. 



