11 



These names are used in the following report. 



Since the conclusion of his work on the St. John group, the writer 

 has been engaged in studying and developing the faunas of the 

 Division ' ' of the classification given in 1882 for the St. John 

 Cambrian. This division proved to be of much greater importance 

 than it appears to have in the St. John section, and its extension 

 eastward was studied in connection with that of the St. John group. 

 At the eastern end of the St. John basin of Cambrian rocks a full 

 exposure of its measures was found, where it exhibited two divisions 

 with a conglomerate bed between, but the few organisms obtained 

 were not of a sufficiently high order to afford any definite means of 

 comparison with the faunas of other countries. Considerable time 

 was given to the examination of these measures in 1888, and it was 

 then spoken of as the Basal series.* 



Observations on this part of the Cambrian system were continued Regional 

 in the island of Newfoundland, where it was found to contain fossils Etcheminian 

 in better preservation and greater vai'iety. The finding of a dis- * r the oldest 

 tinctive fauna in this group of beds in Newfoundland made it advis- sediment 

 able to give it a distinctive name, as has been done with the several Brunswick 



divisions of the St. John group, and it was called Etcheminian. The ? 



n r . foundland. 



observations made during the past three seasons in Cape Breton have 



served greatly to enlarge our knowledge of this portion of the Cam- 

 brian. 



It is proposed to describe the distribution and thickness of the 

 several groups of Cambrian strata, above defined, as they appear in 

 Cape Breton, but before doing so it will be desirable to refer to two 

 other groups which underlie them, one of which, the Coldbrook, is 

 closely connected with the Etcheminian. The other is an entirely 

 different and much older series. 



PART I. STRUCTURAL GEOLOGY. 



TERRANES REPRESENTED IN THE CAMBRIAN SYSTEM IN CAPE BRETON. 



When the writer began the study of the Cambrian system in Cape 

 Breton (represented on the geological map as Lower Silurian), he found 

 that one series of rocks comprehended in the section coloured as Silurian, 

 was remarkably like the ' Upper Series ' of the Laurentian area near 

 St. John. An examination of the exposures of these beds at Long 



*Trans. Royal Soc. Can., vol. vii, sec. iv, p. 135, 1889. 



