REPORTS OF RESEARCH COMMITTEES. 353 



A study of the origin cf the different elements of the New 

 Zealand flora and the dates of their intrcdiictions should furnish 

 some ideas as to the climate at various epochs during the Tertiary 

 era. Unfortunately there is at the present time no consensus of 

 opinion among botanists as to the time or method by which the 

 various elements were introduced intc the area. Cockayne, in the 

 second edition of his New Zealand Plants and Their Story, quotes 

 Skottsberg with approval and accepts his division ol the New 

 Zealand flora into (1) a Palseo'zealandic element, (2) a Sub- 

 antarctic element, aird (3) a Malayan element, and considers that 

 they appeared in New Zealand in that order. The zoological evi- 

 dence for land connexions, however, indicates that the Malayan 

 bridge was broken early, certainly by the older Tertiary, soi that 

 this element must have appeared in all probability at that time. 

 Also the plant beds of Seymour Island, with their remains of 

 I'ndncarims, Nothofar/itu, Drimys^ Knicihtia, &c., contain elements 

 of Skcttsberg's Palaeozealandic flora, which no doubt existed over 

 a wide area in early and mid-Tertiary times, when a mild climate 

 must have obtained over certain sub-polar lands. This coincides, 

 too, with the warmer mid-Tertiary climate in the New Zealand 

 area. Cockayne evidently considers that the sub-antarctic element 

 was introduced early, but notes a difficulty in connexion there- 

 with, if it be granted that New Zealand in Tertiary times con- 

 sisted of a group of islands, of no great elevation, located in a. 

 warm te^mperate sea. If the islands were high they would 

 naturally afford sanctuaries for the introduced sub-antarctic plants. 

 But Cockayne evidently considers it a pcssibilitv that the ex- 

 tension of this element into tha North Island may have been post- 

 glacial after all, and, therefore, it may be that the sub-antarctic 

 element was introduced to the New^ Zealnnd area last of all and 

 it must have been introduced during a cr Id period. It is evident 

 that the position as stated by present-day botanists is far from 

 clear. 



It should be noted at this stage that Captain Hutton always 

 maintained that the period cf tire extension of the New Zealand 

 glaciers coincided with the Early Pliocene, although he has not 

 been followed by any geologist of note. As he credited the 

 glaciers to increased elevation of the land and did not demand 

 refrigeration, his statement has little bearing on the climate of 

 that time. He further maintained that there was no marked re- 

 frigeration of the climate at the end of the era, but a steady 

 decline in temperature till the present. 



The hypothesis put forward by Speight in his ])aper on the Pmt 

 Glacial Climate of Canterhury (Trans. New Zealand Inst., vol. 43, 

 1911) that succeeding the glacial extension there was a more 

 pluvial climate in this area, is supported by the discovery of 

 stumps and trunks belonging to a former Totara forest buried 

 under the gravels of l.ie Canterbury Plains, near Riccarton. It 

 i« clear that under present climatic conditions this tree and others 



