1865.] APPENDIX DAWSON ON EOZOON. 127 



dissolved in surface-waters, or in those of submarine springs, upon 

 the calcareous and magnesian salts of the sea-water. Experi- 

 ments undertaken with the view of determining the precise con- 

 ditions under which these and similar silicates may thus be formed, 

 are now in progress. 



Appendix to Dr. Dawson's Paper (pages 99 — 111). 



Since the above papers were published, I have had opportunities 

 of examining slices and decalcified specimens of Eozoon from Petite 

 Nation, the locality which afforded the specimens referred to by Dr. 

 Carpenter (pages 112, 116), and I have much pleasure in adding 

 my testimony to his observation of the distinctness of the proper wall 

 of the chambers from the supplemental or intermediate skeleton, 

 as exhibited in these specimens. In the specimens previously 

 examined I could not distinctly ascertain that the structure of the 

 proper wall had been preserved, except in a small fragment from 

 Burgess, not certainly known to be of the same species with the 

 specimens from Grenville. Although I believed that such a 

 distinction must have existed, I could not affirm that it had been 

 preserved. I therefore regard these additional structures, ascer- 

 tained by Dr. Carpenter, as affording strong confirmation of the 

 foraminiferal nature of Eozoon, and as indicating its high rank in 

 the order of Foraminifera ; while at the same time no more satisfac- 

 tory guarantee for the correctness of the observations made here 

 could be given, than the concurrence of one whose authority in 

 such subjects is deservedly so high. 



It is also gratifying to find in recent British publications,* notices 

 to the effect that Mr. Sanford has found the structure of Eozoon 

 in the Laurentian limestone of Ireland), the Connemara marble of 

 the Binabola Mountains) already referred to on page 111. Mr. 

 Sanford's specimens have been further examined by Prof. Rupert 

 Jones, who says : " except that the serpentine replacing the sarcode 

 is lighter than in specimens furnished by Sir William Logan, there 

 is no real difference between the two." Eozoon Canadense will thus, 

 in all probability, be found to be characteristic of the Laurentian, 

 and possibly of a particular portion of that series on both sides of 

 the Atlantic, and will become important to palaeontologists as a 

 means of recognizing rocks of this early life-zone. It would appear 

 also that in Ireland as in Canada the remains of the creature have 



* Geol. Mag., Nov. 1864; Reader, Feb. 25, 1865. 



