PREFACE. 
English Botany and British Mineralogy being now 
nearly finished, it is the desire of many, that those 
plants of ancient formation, which have been pre- 
served in the rocks may be elucidated. I have long 
been attentive to the subject, and hope to indulge 
my friends and myself in a short time. 
At present the digging for the Archway at High- 
gate, having led to many unexpected discoveries, 
and causing a still louder call for the Elucidation of 
the remains of Shells, I do not delay to publish them, 
especially as they greatly help to form a catalogue 
that includes many other habitats, even some foreign 
ones, so that when this work is complete, very little 
will remain to be done to include what are foreign, 
as one place will identify another through the whole 
known world. 
