12 THE LESSON OF EVOLUTION 



which they called Eozoon, had been discovered a 

 few years previously in the Laurentian rocks of 

 Canada; but the announcement, at first received 

 with favour, has, as I shall presently explain, fallen 

 into discredit. Other discoveries, however, have 

 proved more satisfactory. So far back as 1864 Mr. 

 E. Billings found fossils in Newfoundland, which 

 both he and Sir W. Logan thought at the time to 

 be Cambrian, but which have since (in 1888) been 

 shown to be pre-Cambrian. In 1883, and again in 

 1890 , Professor Walcott announced the discovery of 

 undoubted organic remains in the pre-Cambrian of 

 Arizona. In 1889 Dr. G. F. Mathew read a paper 

 to the Eoyal Society of Canada on some lower 

 Cambrian fossils from New Brunswick, which are 

 now, like those from Newfoundland, considered to 

 be pre-Cambrian. Also, in 1892, Dr. C. Barrois 

 discovered supposed radiolarians and sponge-spicules 

 in the pre-Cambrian rocks of Brittany, descriptions 

 of which were published in 1895 by Dr. Cayeux. 



Here, at last, we seem to have reached a palseon- 

 tological base ; for although radiolarians and sponges 

 are not the lowest of animate, they are the lowest 

 which contain any hard parts capable of being pre- 

 served, and are, therefore, the lowest in organisation 

 of any animals we can hope to find fossil. Their 

 position too is, probably, in the oldest system of 

 rocks in which we can ever hope to recognise fossils ; 

 and they are, no doubt, as old or older than any other 

 known organisms. Consequently, the palasontolo- 

 gical sounding-line appears to have touched the 

 bottom. A glance at what we know, or what we may 



