192 REPORT OF THE AMERICAN COMMITTEE. 
(iii.) The rocks below this break have not as yet been satisfac- 
torily classified, but these three stages of progressive metaiuorph- 
ism, which, as Professor Bon ney remarks, in a paper above alluded 
to, have a certain chronological value. 
(iv.) No break has yet been satisfactorily proved to exist in 
Britain between two divisions of these highly metamorphic rocks. 
[Note. — To this report was added another appendix, embodying the verbatim 
replies of some whose opinions were quoted by the reporter. As these are all 
condensed and embraced in the body of the report, they are omitted here. — 
Eds. Geologist.] 
