646 



MESSES. CLOTJGH, MATJEE, AND BAILEY OK [Xov. 1909? 



alignment of the dykes, and are also tangential to the margin 

 of the Etiye Granite. Outside these lines only a few sporadic 

 dykes are found ; these stragglers, however, maintain the normal 

 north-north-east and south-south-west direction, and afford no 

 indication whatever of a tendency to radial grouping. We may 

 draw the conclusion, therefore, with some confidence, that the 

 abundance of the north-north-east dykes in Glen Coe 

 is little more than a coincidence, and that these dykes 

 have their focus in the heart of the Etive Granite. 



A suggestion as to the relationship of the dyke-swarms to this 

 focus will be made in the theoretical discussion at the end of this 

 paper (p. 673). 



5. — Map showing the distribution of the local dykes 

 of Glen Coe. 





\ 



-v. 





7v 





F, faults 

 — dykes 





V 



\T 









\ \ 



\_ 



\ 



\ 



V 







V 



1 



1^" 







fJjf 



lO .' 



|2 



,3 ,4 



iS 



|6 ,7 



,8 TtfilM 





In addition to the great swarm of north -north-east dykes in Glen 

 Coe there are a few which are of earlier date. They have a local 

 distribtition, and obviously are closely connected with the Glen Coe 

 centre (fig. 5). 



They are often of lava types and follow no common direction. 

 They are also invariably cut by the north-north-east porphyrite 

 dykes. Definite evidence of the early date of several felsites 



