*58 
The Ancient Fauna of Essex. 
[and also the brick-earth, H. AY.] is not of definite age, bnt 
may have been forming at any time since the last emergence 
of the country from the sea (and its consequent subjection to 
atmospheric agents) to the present time." 
This theory of the atmospheric origin of the clay with flints, 
and so of the brick-earths of the chalk-area, was put forward 
by my friend, Mr. W. Whitaker, B.A., F.G.S., in the Geo¬ 
logical Survey Memoir to Sheet 7, 1864, and I thoroughly 
endorse his views. 
This brick-earth would be slowly formed upon the upper 
watershed of the Thames and all its tributaries, and by rains 
and floods would be washed off the surface and brought down 
into the quiet reaches, together with the bones of land- 
animals, and land-snails. 
The story of the Thames Valley brick-earths is the same as 
that of the “red-earth ” of our ossiferous caverns in limestone 
districts. The carbonate of lime is dissolved away by the 
percolation of rain-water charged with carbonic acid, eating 
out those great swallow-holes, chasms, and caves for which 
the Mendip Hills, the Peak in Derbyshire, and the limestone 
districts of Lancashire and Yorkshire are so famous. This 
red-earth of the caves is only the insoluble (aluminous) 
residuum of the limestone in which, as in our brick-earths, 
the relics of prehistoric man and of the animals he saw and 
hunted have been found. 
The following is a list of the Mammalian remains from 
Ilford, from the collection of the late Sir Antonio Brady, 
F.G.S., now preserved in the British Museum of Natural 
History:— 
Felis spelcea. 
Canis vulpes. 
Ursus ferox. 
Elephas primigenius. 
,, antiquus. 
PJiinoceros leptorhinus. 
,, megarhinus. 
,, ticliorhinus. 
Equus fossilis. 
Megaceros hibemicus. 
Cervus elaphus. 
,, sp. 
Bison prisons. 
Bos primigenius. 
Miscellaneous Ruminant re¬ 
mains. 
FLippopotamus. 
Undetermined species. 
