Extracts from the Minute Book of the Geological Soeicty. 449 



concretions of a rather flat and small botryoidal external figure of 

 an iron black colour, and highly metallic lustre, resembling grey 

 manganese, or black hematitic iron ore. 



Intermixed with these are small arborescent tufts, about a quarter 

 of an inch in length, adherent by their base to the mass of coak, 

 each branch of which, when examined by the microscope, appears 

 composed of minute botryoidal shoots. 



