290 Canadian Record of Science. 



These Canadian anorthosites, on the contrary, show with 

 the cataclastic structure the following peculiarities : — 



1. This structure occurs not along definite lines, but 

 throughout the rock. 



2. Where it occurs there is neither saussurite nor 

 uralite. However granular the plagioclase may be, no 

 trace of saussurite can be seen. In like manner, no uralite 

 is detected, even though the granulation of the pyroxene 

 is so far advanced that only the smallest remnants of the 

 original individuals remain. Now and then some small 

 grains of compact hornblende occur with the pyroxene in 

 the neighbourhood of the contact with the gneiss, exactly 

 as in many normal gabbros. But even these are by no 

 means invariably present; the finely foliated rock, con- 

 sisting of alternate layers of unaltered pyroxene and 

 plagioclase, while remnants of the large individuals of 

 both are constituents, from which the granulated portion 

 has originated are still seen. The only place in which 

 saussurite occurs is, as above mentioned, near New Glasgow. 

 It forms here, like epidote, strings and veins, which have 

 no relation with the foliation of the rocks, but represent 

 small crushed zones, which have originated at another 

 much later period. These very occurrences show most 

 distinctly how different the products of the normal 

 dynamic agencies are from the structure now under 

 consideration. 



3. In the main portion of the area, the granulation is 

 not accompanied by foliation, and we can observe in the 

 large weathered surfaces, plagioclase individuals which are 

 in the act of breaking in every possible direction. It is 

 evident, therefore, that they were not acted upon by 

 forces, such as would result from movements in a mass of 

 a more or less pasty consistency. In the arm -like exten- 

 sion from the south-east part of the area where the rock, 

 as already mentioned, is often distinctly foliated, this 

 foliated structure originated, as shown by a careful study, 



