INTRODUCTION. XXV 



system " preserved in malacolite " (A.D. 1869) . ( ' I confess that 

 until I can examine such specimens, which I have not yet met 

 with, I cannot, after my experience of the tendencies of Messrs. 

 Rowney and King to confound other forms with those of 

 Eozoon, accept their determination in a matter so critical and 

 in a case so unlikely." Brief reference is made to the occur- 

 rence of " Eozoon" in the Connemara ophites; but as these 

 rocks are by most geologists believed to be post-Laurentian, 

 and there are considerations connected with the presence therein 

 of the presumed fossil unfavourable to its organic origin, the fact 

 of course must be got rid of. Dr. Dawson, although having him- 

 self observed " traces of organic structure " in the Connemara 

 marble (A.D. 1865), and having joyfully accepted the corrobo- 

 rative evidences discovered by Sandford and T. R. Jones (A.D. 

 1864), suppported also by the testimony of Dr. Carpenter (A.D. 

 1867), and in presence of perfect examples made known by 

 ourselves (A.D. 1866, 1869), now declares, {< I have never been 

 able to satisfy myself of the occurrence of any definite organic 

 structure in the Connemara specimens " \ 



Messrs. King and Rowney on Eozoon Canadense. Dr. T. S terry 1870. 



Hunt. Proc. Roy. Irish Acad. ser. 2, vol. i. pp. 123-127. 

 The writer will " not even admit the pseudomorphous origin 

 of serpentine itself, but believes that this, with many other 

 related silicates, has been formed by direct chemical precipita- 

 tion." Dr. Hunt has asserted the same of limestones : they 

 " owe their origin to chemical precipitation ; " " the often 

 repeated assertion that organic life has built up all the great 

 limestone formations is based on a fallacy," "the occurrence 

 therein of shells, corals, and Eozoon is only accidental." These 

 dicta on the origin of limestones having been thus dogmati- 

 cally pronounced, notwithstanding that many geologists (Ram- 

 say A.D. 1868, Hull A,D. 1869) had accepted the creature of 

 the dawn" on the faith of its explaining the origin of the 

 calcareous masses of the Laurentians, we brought under the 



