THE APPEARANCE OF LIFE ON THE GLOBE 335 



rocks. A part of the sediments must even have 

 been entirely digested and incorporated into the 

 internal magma, thus losing every trace of the 

 original foliated structure. The entire basis of the 

 series of sedimentary strata deposited in the earliest 

 seas is probably destroyed by this process, and de- 

 finitively withdrawn from our observation. 



What is there astonishing, then supposing this 

 theory of a general metamorphism to be correct 

 in the fact of all traces of organisms having entirely 

 disappeared from those Archean strata which 

 living beings had to abandon at the time of the 

 deposit of these strata in the early oceans ? In 

 fact, the crystallophyllian series, which, at some 

 points of the globe attains a thickness of more than 

 20 kilometres of superposed strata, seems entirely 

 devoid of fossils, and it appears very improbable 

 that any will ever be found therein. 



Yet, nearly half a century ago, a glimpse of 

 hope on this question appeared. The Canadian 

 geologists, when studying the Archean layers on 

 the shores of the St. Lawrence, remarked on the 

 surface of a bed of serpentine limestone, inter- 

 calated in the early gneiss, some protruding 

 nodes jutting out in semi-relief and of varying 

 dimensions extending to the size of a child's head. 

 Examined microscopically in sections, these nodes 

 showed themselves formed of thin concentric and 

 alternate bands of calcite and serpentine, the first 

 being traversed, besides, by a system of perpendicu- 

 lar and ramified tiny canals. Eminent palaeonto- 

 logists, such as Dawson and Carpenter, thought 

 they could see in these kidney-shaped lumps the 



