FOSSIL DICOTYLEDONOUS TREES. 203 
_ very remarkable fossil fruits that are occasionally met with 
_ in the White Chalk of Sussex and Kent, and appear to belong 
_ to dicotyledonous trees. The first specimen was discovered 
q by me in a chalk pit near Lewes, and is described in my 
_ “ Fossils of the South Downs :” some illustrative examples 
; collected by Mrs. Smith, of Tunbridge Wells, tending to eluci- 
date the nature of the original more satisfactorily than those 
in my collection, are figured and described by me in the 
, Journal of the Geological Society, 1843, under the above 
name. These fruits are of an oval form, about one and a half 
inch long, and one inch wide, and are pressed almost flat. 
; They are of a rich burnt-sienna colour, mottled with white, 
_ from the chalk having permeated their substance, and are 
_ studded over with slight eminences, which are the exposed 
summits of oblong flattened seeds. Although the internal 
- structure is not preserved, there can be no doubt that the 
_ originals were spurious compound berries, having, like the 
_ Mulberry, the seeds imbedded in a soft pulpy mass. 
__ Fossiz DicoryLeponous TreEes.—The occurrence of trunks 
and branches of angiospermous trees in a carbonized state 
has already been described ; like the monocotyledons and 
_ conifers, they also occur silicified. 
The most beautiful specimens I have seen are from the 
_ Lybian and Egyptian deserts, and were collected by my friend, 
the late Colonel Head. In these the most delicate vascular 
_ tissue is permeated by chalcedony and jasper, and the vessels 
are filled with silex of a bright vermilion and blue colour, 
_ while the cellular structure is of a rich yellow. Fragments of 
_ these fossil trees are scattered everywhere among the sands 
_ Of the desert ; the most interesting locality is an irregular pla- 
_ teau, which reposes on marine limestone, considerably above 
the level of the Nile, about seven miles east by south from 
Cairo. This district is called the petrified forest, from the 
immense quantities of silicified trees with which it is covered. 
It is thus graphically described by a late traveller :— 
