PREFATORY NOTICE. 



As the few photographic illustrations which are 

 introduced in the following pages, helpful as they 

 are, afford at best only a defective and imperfect 

 idea of the evidence, compared with the sight and 

 examination of the numerous flint specimens them- 

 selves, these the writer will be happy to submit, as 

 far as can be arranged, to the inspection of any one 

 interested in the study, who will favour him with 

 his card, and a call at such a time as he may be at 

 home for the purpose. 



