THE HISTORY OF A DISCOVERY 



133 



I was not content with examining the typical 

 specimens of Eozoon, but had slices prepared of 



Fig. 2%.^Group of Canals in the Supplemental Skeleton of Eozoon. 

 Taken from the specimen in which they were first recognised. (Magnified.) 







i^^^^im 



Fig. 29. — Canals of Eozoon^ from same specimen, 



(Highly magnified.) 



every variety of Laurentian Hmestone, of altered 

 limestones from the Cambrian and Silurian, and of 



