15? 



The species all come from the Etcheminian sandstones and shales, and 

 from a body of shales included in the volcanic rocks which underlie 

 them. This part of the Cambrian appears to contain three faunas, one 

 in the shales of the volcanic rocks, and two in the Etcheminian sediments. 



Only two species of Ostracoda have been found in the shales of the 

 volcanic rocks, so that the bulk of the fauna is Etcheminian. The dis- 

 tribution of the forms throughout this series of beds will be readily seen 

 by the accompanying table. The three larger divisions of the Etchemi- 

 nian shown in the table are lithological, and the Lower Etcheminian 

 Fauna is confined to the two lower divisions ; the Upper Fauna is in III 

 of the upper division. The letters beneath these divisional spaces indi- 

 cate the successive assises in which fossils have been found. No Ostra- 

 coda of the Protolenus Zone have been recognized in these beds, and so 

 it is supposed they are older than that fauna. 



LIST of Ostracoda of the Coldbrook and Etcheminian terranes in Cape 

 Breton with the horizons at which they are found. 



