ASSOCIATED ROCKS OF PORTHALLA COVE, Ae 
the intrusion of the serpentine between the beds of hornblendic 
schist. Whatever doubt there may be about Porthalla Cove, 
where it is difficult to study the relation of the rocks, there are 
localities in the district in which the intrusion of the serpentine 
into the schists can be made out without the smallest possibility of 
doubt. 
Mr. T. Davres regretted the absence of microscopic sections in 
illustration of Mr. Collins’s paper. His own study of the question 
had led him to conclusions quite opposite to those of the author, 
He thought the Lizard serpentine showed under the microscope 
clear proof of its derivation from an igneous rock. 
Mr. W. W. Smuyru agreed with Prof. Bonney and Mr. Hill as to 
the clear evidence of the intrusion of the serpentine into the schist, 
At the same time there are undoubtedly points at which there 
appears to be an interlamination of the serpentine and the schists ; 
but this is no proof whatever of transition from one rock to the other. 
He could not understand this transmutation taking place along 
narrow bands for hundreds of yards without the beds above and 
below being affected. He did not feel able to accept such dis- 
putable sections as those shown by the author as explaining the 
complicated relations of these two rocks in the Lizard district. 
