president's address — SECTION c. 51 



general history. The following is an attempt to do this as far 

 as possible within the limits of an address. It is not, like its 

 predecessors, based on long personal investigation, but is rather a 

 revaluation of the recorded facts, made in the light of the investi- 

 gations of the last decade, by an Australian geologist whose lot 

 lias now fallen in the pleasant places of New Zealand. Grateful 

 acknowledgment must be made of the help afforded by those who 

 have placed at the writer's disposal information published and 

 unpublished, and the original material of certain investigations. 

 Among these are Mr. Morgan, Director of the Geological Survey, 

 to whose geuerasity I am indebted for the accompanying map 

 correlation tables, Dr. Marshall, my predecessor in the Otago 

 University, and in this Presidential Chair, Dr. Thomson of the 

 Dominion Museum, Dr. Henderson, of the Geological Survey, and 

 my University colleagues. Professor Park, Mr. Speight, Mr. Bar- 

 trum, and especially Dr. C. A. Cotton, to whose guidance I owe 

 much of my field knowledge of New Zealand Geology.* 



The geological histoiy of New Zealand falls into three major 

 periods, the oldest of which may be considered to have closed about 

 Carboniferoius times, and the second in Lower Cretaceous times, 

 and the third at the end of the Pliocene period. The record of 

 the first is very fragmentary and by no means free from doubt, 

 nor is it always sharply separable from that of the second period. 

 The detailed history of the second major period has been greatly 

 elucidated during, the last decade. In regard to thei sequence of 

 events in the third and chiefly Cainozoic major period, there has 

 not been much doubt as to the sequence of formations in any one 

 area, but there have been frequent changes in the interpretation 

 and correlation cf these formations in different areas, upon which a 

 flood of light has been thrown by the new rapidly accumulating 

 observations and newer conceptions. We may perhaps recognise a 

 fourth period, the cycle of events just initiated by the recent move- 

 ments oif differential elevation, which have been the subject of de- 

 tailed physiographic study, particularly by Dr. Cotton. In all 

 countries in the earlier stages of geological investigation, often car- 

 ried on under great disadvantages, many interpretations have been 

 given. This is especially true of New Zealand, and in the diver- 

 sity of these statements, and the frequent changes of nomenclature, 

 lies the greatest difficulty to be faced by those attempting to find 

 a clear path through the older records. Tabular statements of 

 the principal interpretations of the three major periods are given 

 herew;ith, and may serve to elucidate some of the complexities in 

 the older literature. Differences of opinion still exist, but must 

 steadily decrease as the accumulation of facts limits the range of 

 permissible speculation. 



* The manuscript of this aridress was kindly read by Mr. Morgan. Dr. Cottoij, and 

 Dr. Henderson. 



