xlii 



INTRODUCTION. 



of the variety called " moon- stone/' is obliquely intersected by 

 what appear to be laminae of a triclinic feldspar, inasmuch as 

 they are crossed with striae : similar laminae are seen in the 

 specimens of orthoclase represented in fig. 4, PI. I. Our 

 figure of Dr. Heddle's specimen affords but a poor idea of its 

 beauty and remarkable structural character. 



1876. Notes on Otto Hahn's Microgeological Investigation of Eozoon 

 Canadense. Dr. William B. Carpenter. Ann. & Mag. 

 Nat. Hist. ser. 4, vol. xvii. pp. 417-422. 



1876. Eozoon Canadense according to Hahn. Dr. J. W. Dawson. 

 Ann. & Mag. Nat. Hist. ser. 4, vol. xvii. 



1876. Review of Dr. Dawson's ' Dawn of Life.' T. R. J. Geol. Mag. 

 Decade II. vol. iii. April 1876. 



1876. Note on the Geological Position of the Serpentine Limestone of 

 Northern New York, and an Enquiry regarding the Relations 

 of this Limestone to the Eozoon -limestones of Canada. 

 Prof. James Hall. American Journal of Science, 3rd ser. 

 vol. xii. pp. 298-300. 



Noticing the lower division of the Laurentian rocks in 

 Northern New York, Prof. Hall states that they are "uncon- 

 formably overlaid by massive beds of gneissic and labradoritic 

 formations, associated with which are one or more bands of 

 crystalline limestone : the latter " is usually and perhaps always 

 permeated by serpentine in grains, bands, or what sometimes 

 appear as concretionary or aggregated masses of that mineral." 

 This serpentine limestone " has been reported as containing 

 Eozoon" ..." The simple point which I wish to demonstrate 

 is that this limestone" of Northern New York "does not 

 belong to the Laurentian limestone, either Lower or Upper, 

 that it is a formation deposited along the flanks of and within 

 the Laurentian area, at a ^period subsequent to the deposition, 

 metamorphism, and disturbance of the rocks of authentic 

 Laurentian age, and that it apparently holds a place in the 



