98 FOSSILS FROM THE UPPER GREENSAND. 



The stony lumps in the top bed of sand are remarkable for 

 enclosing fragments of brown phosphate of lime and green-coated 

 phosphate nodules. 



Further west, near Stoke Wake, this bed has become a nodular 

 calcareous sandstone, that is to say the whole mass is cemented by 

 calcite into a sandstone, instead of being merely a sand with 

 calcareous lumps, but the phosphate nodules are still only in the 

 upper part. 



At Melcombe Bingham the rock-bed is six feet thick, and the 

 phosphatic portion is about two feet ; the latter is crowded with frag- 

 ments and nodules of brown phosphate with casts of fossils in the 

 same- material, besides which there are many fossils in an ordinary 

 state of preservation, having shells of calcite (or carbonate of lime). 



The lower part of the sandstone also contains fossils, among 

 which Pecten asper, Janira quadricostata, Exogyra conica, and 

 Ostrea vesiculosa are most frequent. 



The upper surface of the rock is generally uneven and waterworn 

 with cracks and hollows, which are filled with the material of the 

 overlying glauconitic chalk, the so-called " Chloritic Marl." The 

 sides of ihese cracks are often covered with small Serpulce, young 

 oysters, and Plicatulce, showing plainly that the rock was exposed 

 for some time to the action of a current in clear water before the 

 chalk began to be deposited upon it. 



Moreover fossils belonging to the " Chloritic Marl " or basement 

 bed of the Chalk occur in the cracks and hollows of the sandstone, 

 and would naturally be regarded as belonging to the latter by any- 

 one who was not aware of the possibility of mixture. The chalk 

 phosphate, however, is much lighter in colour, having generally a 

 buff tint and the adherent matrix is a soft, fine-grained marl. 

 Many of the Chalk fossils were collected and mixed up with those 

 from the sandstone, but in working through the Museum collection 

 I have separated these out and have relegated them to their proper 

 place in the Lower Chalk series. 



The sandstone-rock maintains the same thickness of about six 

 feet along the outcrop west of Melcombe Bingham, but the thickness 



