THE CRYSTALLINE ROCKS NEAR ST. JOHN, N. B. 33 



Summary. 



To sum up, finally, we have represented at St. John, 

 besides the ordinary sedimentary strata, the following 

 types of rock : 



1. A varied series of metamorphic or crystalline stratified rocks. 



2. Intrusive rocks, both acid and basic, showing well the phenomena 



of contact-metamorphism and segregation. 



8. A. great and varied series of volcanic rocks — lavas, breccias and 

 ashes — all of pre-Cambrian age. 



4. Dykes, mostly trap (diabase) and with some exceptiong also of 

 pre-Cambrian age. 



Explanation op the Map. 



I am indebted to the courtesy of the ISTew York 

 Academy of Science for permission to use the plate for 

 this map, which first appeared in connection with my 

 article, read before that body, on April 16th, 1894. 



The reference column in the margin will sufficiently 

 show the meaning of the various markings used in the 

 body of the map. J^o attempt has been made to dis- 

 tinguish the bands of limestone in the Laurcntian rocks, 

 as this would necessitate a more detailed survey of the 

 district than it has been possible to make. Areas where 

 the limestones have been found are not specially distin- 

 guished here, but are designated in a general way on the 

 map of the Canadian Geological Survey. 



