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are very basic and cannot therefore, it is thought by the authors, be in 

 any way considered to be derived from the protogine by dynamic 

 action, but are to be considered as sediments, depressed by a syncHnal 

 fold and bounded by the protogine on either side. The whole series 

 of rocks, both protogine and surrounding schists, are penetrated by a 

 series of more recent granite veins or dykes, and these it is believed 

 have brought about the profound metamorphism of the surrounding 

 rocks, injecting and "granitizing the schists everywhere in the vicinity 

 of the protogine, so that the gneissic zone which immediately borders 

 the protogine is not in any way connected, genetically, with the pro- 

 togine itself, but results from the profound alteration of the mica 

 schists surrounding the protogine by these newer granite dykes. The 

 varying character of the different schistose rocks in this gneissic zone 

 is considered to be due to the varying resistance offered to this "granit- 

 izing" action by the different beds in question. Thus, for instance, 

 the eclogites retain their basic character and have not been transformed 

 into orthoclase gneiss, because they are too compact to allow of -a free 

 circulation through them of the solutions producing the alteration. In 

 the paper by Duparc and Mrazec, a number of analyses of the several 

 varieties of protogine and granitized schists are given. 



The crystalline schists of eastern Sutherland, described by Messrs. 

 Home and Greenly, consist of a series of gneisses, granulites, mica 

 schists, etc., some few members of which show conclusive evidence of 

 a sedimentary origin while the origin of others is doubtful. The whole 

 series has been intensely deformed. Not a cubic inch can be found 

 which has not suffered deformation, but distinct cataclastic structure 

 is not seen, so that recrystallization must have taken place during or 

 after the movements. The series is invaded by masses of intrusive 

 granite, which have broken across the schists, anastomozing through 

 them and often penetrating them as a series of thin leaves, parallel to 

 their foliation, in the manner termed by the French writers /it par lit 

 injection. The boundary between the injecting granites and the schis- 

 tose series is often rather ill-defined, owing to the fact that the granitic 

 constituents seem to interlock with those of the wall rock with which 

 they are in contact. The granite never shows any finer grained sahl- 

 band, indicating injection to a cold rock, but is usually coarse-grained 

 and pegmatitic on the borders. It seems reasonable to infer, therefore, 

 that the igneous material was introduced when earth movements were 

 in progress and when the countrv rock was at a high temperature. 



