262 F. H. Lahee — Metamorphism and Geological Structure, 



(6.) Variations in the deformation, due to vertical position in 

 the folds, are of little importance and are commonly local. 

 The folding appears to be of the parallel type except in rare 

 instances of very minute crumpling. 



(7.) The factors upon which variations in the folding are 

 dependent, mentioned in order of lessening importance, are : 



(a) relative position of outcrop along north-south lines ; 



(b) rock texture ; 



(c) distance of outcrop from walls of Basin ; 



(d) relative vertical position of outcrop in fold. 



Cambridge, Mass., Jan. 6, 1912. 



(To be continued.) 



