Radium.] SUBANTARCTIC ISLANDS OF NEW ZEALAND. 781 



porphyrite approaching an augite-camptonite in character and composition, found 

 penetrating the more recent basalts. The age of these basalts is probably from 

 middle to late Tertiary. There is no marked difference between the earlier and 

 later basaltic flows, but the one from sea-level at Adams Island is fine-grained and 

 contains hornblende, while the other is very coarse-grained, with large phenocrysts 

 of olivine and augite. 



The Campbell Island limestone is of Tertiary age and markedly foraminiferal. 

 The marble is derived from it as a result of basic intrusion. 



A general conspectus of these results shows that the Ra content corresponds 

 roughly with the basicity and not with the age of the rocks. 



