Stromatoporoids and of Eozoon. 453 



about which the greatest experts differ, viz. the problem of 

 the aqueous or igneous origin of many of the metamorphic 

 rocks, I would stute my belief in the aqueous origin in some 

 cases. At the same time I recall the sandwiched layers of 

 Miocene coral-reef and lavas in tlie Bai.xo Island near Porto 

 Santo, which might in some respects be compared to Archseaii 

 Foraminifeial reefs and layers of rock (gneiss) of possible 

 igneous origin. Wiiether it is possible or not for lava to 

 become metamorphosed so as to resemble gneiss is apparently 

 not definitely known. 



The biological implications are of the deepest interest. 

 The ancestor of Eozoon must have lived immeasurable ages 

 before the appearance of its highly organized descendant. 

 We may imagine that ancestor to have been a naked mass of 

 sarcode, from the periphery of which reticulate pseudopods 

 radiated out. This animal would have been more entitled to 

 the poetic name of Dawn Animal than its descendant, which 

 had travelled some distance along the road since the first 

 glimmer of life's dawn. The real dawn rays (of animal life) 

 were, may one say, the pseudopods of a shell-less Rhizopod 

 (like the freshwater Lieberkuhnia). 



In the next stage towards Eozoon we have to imagine knots 

 on a stolon each forming the centre of a coil, and, lastly, the 

 formation round pseudopods of a highly elaborate secondary 

 skeleton, enclosing the rouleau of coiled shells. 



I wish to express my sincere thanks to my colleague 

 Mr. W. D. Lang, who has taken the greatest trouble in 

 furnishing me with abundant material from among the 

 treasures under his charge. 



Finally, I would express my deep regret that, owing to 

 great pressure of work, I have been able to set forth this 

 important communication only in a very disjointed fashion. 



Appendix. 



Note 1. — In my paper in the September * Annals ' I failed 

 to do justice to Sir W. Dawson, the only investigator wlio 

 definitely stated that Stromatoporoids and Eozoon were 

 Foraminifera. I only noticed his remarks in 'The Dawn of 

 Life,' where he supposes Stromatoporoids to be a connecting- 

 link between Sponges and Foraminifera. But in the Quart. 

 Journ. Geol. Soc. xxxv. pp. 48-66 (not seen by me at ihe 



