270 A., J. JUKES-BROWNE ON THE RELATIONS OF 



noduliferous greensand, not dissimilar to the matrix of the Cam- 

 bridge phosphate-bed. It is thus described by Mr. Price : — 



ft. in. 



(c. Pale-coloured marly clay 17 6 



b. Middle greensand, with nodules 3 3 

 a. Pale grey clay resting on a band of nodules with 



Pecten Baulinianas 35 6 



Total 56 3 



The nodules in this greensand bed are of two kinds, as at Cam- 

 bridge — some black, waterworn, and irregular, others light brownish 

 grey in colour, and evidently formed in the bed itself, since they 

 include glauconite grains and are often attached to the black 

 nodules ; sometimes two or more of the latter are cemented toge- 

 ther by this light phosphate, exactly in the same way as many of 

 the Cambridge coprolites are bound together. 



The fossils of bed XI. are nearly all found at Cambridge ; and 

 among the commonest are Solarium ornatum, Avicula gryphceoides, 

 and Plicalula pectinoides. 



Above the Gault comes a dark green sandy bed, about 10 feet 

 thick, and almost entirely made up of glauconite grains ; this repre- 

 sents the Upper Greensands. It appears to rest with a somewhat 

 uneven surface upon the clay below ; and its contents are mainly 

 sponges of the genus Brachiolites, few other fossils having been 

 found in it. 



The next succeeding bed is of about the same thickness, but much 

 lighter in colour, being a whitish marl with scattered green grains ; 

 this passes into the yellowish grey rock of the Chalk-marl. 



Such is the section in Eastwear Bay ; but when traced inland 

 differences are soon apparent : the dark Upper Greensand thins out 

 entirely in a few miles, allowing, it is said, a thin band of Chloritic 

 Marl to come down on the Gault. 



There are no good sections, however, to be seen until we arrive at 

 Aylesford, near Maidstone, where there is a large brick-pit, in the 

 cliffs of which the following remarkable section is exposed : — 



ft. 



3. Chalk- marl passing down into light green sandy marl 10 



2. Basement-bed of greenish marly sand containing rolled 



black coprolites 1 



1. Bluish grey Gault, with a thin band of brownish clay at 



the top 30 shown 



We have here, then, precisely the same conditions as at Cambridge 

 — namely an absence of Upper Greensand, and a coprolite bed at the 

 base of the Chalk-marl — though the nodules here are not so abundant, 

 and the bed would not pay to work. 



The explanation I consider to be the same in both cases ; and at 

 Aylesford, I believe, it is the removal of the beds representing the 

 top 30 or 40 feet of bed XI. at Folkestone which has caused the 

 above-mentioned appearances. 



About 20 feet down in the clay I found many specimens of Inoce- 

 ramus sulcatus and Ammonites varicosus, which at Folkestone charac- 



