430 ON THE ROCKS OF GUERNSEY. 
inclusion of gneiss-fragments in granite, and suggested that this 
might be regarded as a crucial test as to the granitic nature of the 
rock. 
Dr. Hicks thought with the last speaker that some of the rocks 
might be lava-flows. He said that included fragments, such as are 
common in some Scotch granites, were never found in the so-called 
granitoid rocks of Wales. 
The Presmpent said that in the hornblende-gabbros the horn- 
blende might not improbably be altered augite. The diorites and 
syenites pass into one another by the most insensible gradations. 
The AvrHor said that his paper was in part devoted to proving 
that the views expressed by Prof. Seeley were not applicable to 
these igneous rocks. The felstones of Guernsey were like those of 
Jersey, and it was not impossible that it might be practicable to fix 
the age of those rocks. 
