40 THE CHAIN OF LIFE. 



there may have been forms that would at least enable us to 

 connect Eozoon and Stromatopora. 



Another link in the chain of being remains to be noticed 

 here. In the Laurentian limestones we meet with numerous 

 minute spherical bodies and groups of spheres with calcareous 

 tubulated tests. ^ These may either be small Foraminiferae, 

 distinct from Eozoon, or may be germs or detached cells from 

 its surface. Similar bodies are found in the lower part of the 

 Siluro-Cambrian, in the Quebec group at Point Levis ; and there 

 they are filled with a species of glauconite constituting a sort of 

 greensand rock. Still higher, in the Carboniferous, there are 

 very numerous species of Foraminifera, presenting forms very 

 similar to those of the modern seas, so that in the smaller 

 shells of this group we seem to have evidence of a continuous 

 series all the way from the Laurentian to the present time. The 

 greater laminated forms cc-exist with these up to the I^pcene 

 Tertiary. Throughout the whole of geological time — from the 

 formation of the Laurentian Hmestones to that of the chalky 

 ooze accumulating in the modern ocean — these humble creatures 

 have been among the chief instruments in seizing on the 

 calcareous matter of the waters and depositing it in the form of 

 limestone. 



I have, said nothing of the development of higher forms of 

 animal life from Eozoon, simply because I know nothing of it. 

 We shall see in the next chapter that these are introduced 

 seemingly in an independent manner. We may be content to 

 trace foraminiferal life along its own line of development, 

 waxing and waning, but ever confined within the same general 

 boundaries, from the Laurentian to the present time. It is 

 likely that if, in any of the ages constituting this vast lapse of 

 time, a dredge had oeen dropped into the depths of ocean, 

 it would have brought up Foraminifera not essentially different in 

 form and structure. If any one asks to what extent the suc- 

 cessive species constituting this almost endless chain may be 

 ^ ArchcBospherina of the author. 



