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CHALK FOSSILS. 
Fucoides Brongniarti. 
Dicotyledonous wood is found imbedded in flint, 
and a])pears waterworn, as if drifted : it is com- 
monly marked with perforations from teredines 
and flstulanm. It also is enclosed in chalk, and 
in that state is very friable, and of a deep reddish 
brown colour ; but the more compact specimens 
liave the appearance and texture of Bovey coal. 
ZOOPHYTES. 
Although the remains of this class of organized 
beings are very abundant in the chalk, they are 
referable, comparatively, to but few genera and 
species. The stony corals are for the most jiart 
transmuted into calcareous spar ; while the softer 
spongeous zoophytes are either enveloped in flint 
or chalcedony, or form chalky ferruginous masses. 
On the echini and shells several sjiecies of 
Cellipora and Tlustra occur, but they have not 
been examined with the attention and discrimina- 
