36 JOURNAIv OP THK 



(1) Their blunt, lenticular form is difficult to under- 

 stand as the result of any kind of sedimentation, but is 

 easily explained when they are considered as small in- 

 trusions into a hig'hh^ laminated rock. 



(2) In a number of cases apophyses are sent off into 

 the enclosing- g-neiss— a condition that can be produced 

 only by ig-neous action. 



(3) In one case, at least, a larg-e block is completely 

 enclosed by the peridotites in such a manner as to pre- 

 clude all hypotheses of sedimentation, and attributable 

 only to the intrusion of the peridotites in a molten 

 state. 



(4) The lamination found in many cases which has 

 been considered true bedding-, is always accompanied 

 by abundant evidence of shearing-; and this is reg-arded 

 as the most natural explanation of all such parallel 

 structure in these rocks. 



(5) i^t Buck Creek and in adjoining- reg'ions, both the 

 main masses of the peridotites and their apophyses are 

 accompanied by amphibolite dikes, showing* that the 

 former occupy positions of marked weakness in the 

 g-neisses. 



(6) The massive character of the tj^pical outcrops is 

 incompatible with contemporaneous orig-in with the 

 g-neisses; for such character could not have been main- 

 tained throug-h the intense metamorphosing- processes 

 to which the g-neisses. have been subjected. 



(7) The extremely basic peridotites are enclosed in 

 hig-hly acid g-neisses over an extensive territory, but 

 they are everywhere perfectly separate — no transitional 

 types are found. 



(8) Under the microscope these peridotites show the 

 typical g-ranular structure of plutonic ig-neous rocks, 



