214 RELICS OF PRIMEVAL LIFE 



closely resembles that of Cryptozoon, though it is 

 somewhat obscure. If these are really Huronian 

 and not Laurentian, the Eozoon from this horizon 

 does not sensibly differ from that of the Lower 

 Laurentian. 



We are indebted to Mr. Matthew, of St. John, 

 New Brunswick, who has so greatly distinguished 

 himself by his discoveries in the Cambrian of that 

 region, for some remarkable additions to the 

 contemporaries of Eozoon. One of these is a 

 laminated body, like Eozoon in its general appear- 

 ance, but growing in crowded masses which by 

 mutual pressure become columnar (Fig. 57). In the 

 best preserved specimens each layer seems to consist 

 of a thin lamina separated from its neighbours by 

 a finely granular mass, traversed by innumerable 

 irregular tubes. This recalls the structure of 

 Cryptozoon of Hall, which, as we have seen, is 

 found in pre-Cambrian rocks in Colorado, and 

 abounds in the Upper Cambrian in New York, in 

 Minnesota, and in different parts of Canada, but 

 Archaeozoon differs in its form and habit of growth. 

 If the Stromatoporae of the Ordovician and Silu- 

 rian are hydroids, this may also be the case with 

 Cryptozoon ; but so far as its own structure is 



