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APPENDIX. 



On a former occasion, I stated as my opinion, that all geolo- 

 gical papers ought to be accompanied with specimens of the 

 rocks of which they treated. This is a condition not always 

 to be complied with, unless the intention to write precedes the 

 examination, when a collection may purposely be made ; but 

 when the idea suggests itself, after one is far removed from 

 the district, it amounts nearly to an impossibility. In the pre- 

 sent instance, although I be possessed of all the specimens 

 necessary, they belong to a series which I formed for other 

 purposes. Rather, however, than mutilate this, I have 

 thought it better to present the whole to the Society, in 

 whose possession I shall have an opportunity of referring to 

 them at any time ; and as they have signified their acceptance, 

 it is necessary to add to my paper, the following brief list of 

 the minerals I collected, which are marked and numbered, as 

 picked up on my route, commencing in Somersetshire, where 

 the transition rocks first make their appearance, and ending at 

 Ilfracombe, after traversing Devon and Cornwall in different 

 directions. 



After leaving Bristol, on the road to Exeter, we traverse the 

 limestone ridge of Mendip ; to the south of which, there is an 

 extensive plain, stretching to beyond Taunton, whose unifor- 

 mity is occasionally interrupted by small isolated hills, like 

 islands in a lake. These are probably formed of Transition 



rocks, 



