containing Mammalian Remains. 541 



of the plastic clay shells. The brick-fields belong to four 

 different proprietors ; the first is situated on the right of the 

 road leading from Crayford to Erith, about half a mile north 

 of the former village : it is the property of Mr. Stoneham. 

 The excavation is about 300 feet square, with a depth of 69 

 feet to the chalk, being worked solely for the brick-earth it 

 contains. The following are the beds which occur in an as- 

 cending order, — viz. 



Chalk. 



Rough gravel, quartz, &c... 7 feet 



Sand, (tooth of elephant) 3 feet. 



Concreted sand, with sulphate of lime and veins of re-depo- 

 sited chalk 6 inches. 



Brick-earth with veins, 25 feet. 



Gravel, round and angular, with chalk pebbles, and bones. — 



Varies in thickness , , 1 to 4 feet 



Brick earth; shells , -.7 feet. 



Dark coloured clay, containing shells and bones, {Unio of new 



species probably 6 in. to 2 ft 



The second (Hutchon's) is stratified as follows : — 



Vegetable mould, loam, &c. 3 feet. 



Confused mass of gravel, shells, race, sandy concretions, round 

 and angular flints, cemented by ferruginous sand, irre- 

 gular 4 to 5 feet. 



Sand, more or less wavy, traversed by thin ferruginous veins, 



numerous shells, bones, and brick-earth in patches 6 feet 



Race and pebbles in clay and sand, varying in thickness, and 

 occasionally seen interstratified with wavy veins of sand; 

 bones and shells, — Cyrena, Cyclas, Unio, Sec 1 to 3 feet. 



Brick-earth, few pebbles and concretions 7 feet. 



Loamy sand, with veins of clay 4 feet. 



Gravelly sand 8 feet 



Vein of sand , 1 foot 



Gravel and sand & .. 2 feet. 



Iron flint bed, or bull's head 1 to 2 feet 



Chalk excavated, few flints 14 feet 



Third field, Mr. Clarke's. 



Clay, loam, sand, gravel, broken shells, and concretions, very 



irregular 12 feet. 



Sandy gravel 1 foot. 



Blue and brown clay, here and there veins of small round and 



angular gravel 8 feet 



Loamy sand and concretions 5 feet. 



Pebbles and sandy concretions 1 foot. 



Coarse grey sand with veins of pebbles and broken shells; — 



{Cyrena, Cerithium) 12 feet 



Chalk. 



3 g 2 



