CONTEMPORARIES AND SUCCESSORS OP EOZOON. 135 



oval in outline, about three inches in length, wholly 

 made up of rounded or cylindrical cells, the walls of 

 which have a beautiful tubular structure, but there is 

 little or no supplemental skeleton. Whether this is 

 a portion accidentally broken off from the top of a 

 mass of Eozoon, or a peculiar varietal form, or a dis- 



FIG. 31. Acervuline Variety of Eozoon, St. Pierre. 



('*.) General form, half natural size, (ft.) Portion of cellular interior, magnified, 

 showing the course of the tubulL 



tinct species, it would be difficult to determine. In the 

 meantime I have described it as a variety, " acervu- 

 lina,j" of the species Eozoon Canadense.* Another 

 variety also, from Petite Nation, shows extremely thin 

 laminae, closely placed together and very massive, and 

 with little supplemental skeleton. This may be allied 

 to the last, and may be named variety " minor. 3 ' 



All this, however, has nothing to do with the layers 

 * Proceedings of Geolojical Society, 1875. 



