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REGINALD A. DALY 



also seem to play no role in the petrogenesis of the archipelago. 

 Hence, some of the chief complications in the history of igneous 

 magmas which have invaded the continental plateaus, that is, 

 complications due to the assimilation of such highly varied country- 



Ka 1 LUA 



Fig. i. — Locality map, showing positions of some of the dated lava flows in Hawaii; 

 also original localities of specimens chemically analyzed (dots numbered 1 to 4): 

 1 , gabbro of Uwekahuna laccolith; 2, olivine basalt of 1852 flow; 3, andesitic basalt; 

 4, trachydolerite. 



rocks, here seem to be absent. This relative simplicity of condi- 

 tions makes the petrogenesis of a deep-sea archipelago worthy of 

 attention quite independently of its own intrinsic importance. 

 The problem of origin here becomes largely, though not altogether, 



