ANNIVEKSART ADDEESS OF THE PEESIDENT. lix 



cellular sessile shell-growth, and (2) radiating and otherwise ar- 

 ranged tnbuli in the shell-walls, only represented in recent or 

 fossil forms by the tubular system of the shells of some Forami- 

 nifera. Hence, notwithstanding a few slight discrepancies, Dr. 

 Dawson finds it to be foraminiferal in its character, and therefore 

 refers it to the Ehizopods, with the name of Eozoon Gmiadense. 

 It seems to have attained an enormous size, and by the aggregation 

 of individuals to have assumed the aspect of a coral reef. Mr. 

 Sterry Hunt's paper gives some details of the process by which 

 the original animal matter has been replaced by mineral silicates, 

 which are found not only in the chamber-cells and canals left 

 vacant by the disappearance of the animal matter, but in many 

 cases in the tubuli of the shell- walls. These silicates are pyroxene, 

 serpentine, loganite, and pyrallolite. The pyroxene and serpen- 

 tine are often found in contiguous chambers in the fossil, and 

 were evidently formed in consecutive stages of a continuous pro- 

 cess while the Eozoon was still growing or had only recently 

 perished ; and he concludes by stating his opinion that these 

 silicated minerals were formed, not by subsequent metamorphism 

 in deeply buried sediments, but by reactions going on at the 

 earth's surface. 



It is difficult to overrate the geological importance of this dis- 

 covery. Those beds of enormous thickness which underlie the 

 Lower Silurian and Cambrian deposits, and which, under various 

 forms of gneiss, mica-schist, hornblende-slate, &c., are known 

 under the general term of metamorphic rocks, and have been 

 supposed to have been formed and even re-formed or metamor- 

 phosed before the appearance of animal life on our globe, are now 

 found, instead of being azoic, to contain remains of organic beings. 

 These traces, too, are found in the very lowest depths of those 

 deep-seated beds. The bands of limestone to which they are 

 attached, and to the formation of which they may have contri- 

 buted, occur in the lower subdivision of the Laurentian gneiss. 

 If, then, this Laurentian gneiss represents the first solidified 

 stratum of the earth's crust, we find animal life commencing at 

 the very earliest period after it had attained that state of solidi- 

 fication, of course under water, and before it underwent the pro- 

 cess of metamorphism. Nature appears to have lost no time in 

 availing herself of the newly-prepared field for her operations, and 

 of introducing those forms of animal life best suited to the new 

 condition of the planet, and which having performed their task 

 were destined soon to pass away, and having themselves helped 

 to modify the conditions of life, were to make room for other more 

 highly organized beings adapted to a new state of things. But 

 our astonishment does not cease here. These gigantic Foramini- 

 fera required food and aliment, and although no traces of other 

 organisms have yet been found, we know they must have existed. 

 These animals could not, likeAlgse and other vegetables, draw their 

 sustenance from the rock on which they grew. They required 

 organic matter, whether animal or vegetable, for their food. 



