president's address — SECTION c, 105 



the species of plants in New Zealand find very close allies in 

 Southern America. These co-exist in New Zealand, with a true 

 Malayan element, which must have been here during the close of 

 Mesozoic times, and with a large Australian and Malayan element, 

 which comprises forms of more recent origin which have perhaps 

 entered New Zealand by drift from over seas. (Compare Coc- 

 kayne (1919).* 



Notocene and Recent Volcanic Action. 



We» have already mentioned the outpouring of basic rocks in 

 the Albian series of the Clarence Valley. Thomson (1913, 1919) 

 has suggested that the great series of dykes which traverse the 

 Inland Kaikoura Eange may have been coeval with this out- 

 pouring. To this period also, or perhaps to the Senonian, Mr. 

 Speight would refer the rhyolites of Mt. Somers, the Rakaia Gorge, 

 Malvern, and the Rangitata Valley, pebbles of which occur in the 

 Upper Cretaceous coal-measures of the Malveirn Hills. The rhyo- 

 litic rocks near Lyttleton Harbor are probably coeval. Rather 

 older than these, probably Late Jurassic or Early Cretaceous, 

 (and if not so strictly a part of the Early Notocene volcanicity), 

 are the andesites of the Clent Hills, the Rakaia Gorge and the 

 adjacent Rockwood Range. TTiese were assigned by Marshall 

 (1912) to the Trias- Jura, period, but the investigation now in 

 progress under the direction of Mr. Speight confirms Cox's opinion 

 (1883) that they lie unconformably across the edges of the older 

 Mesozoic rocks. (Speight 1917 and private communications). 



In Middle Tprtiary times, igneous action was still more 

 widespread. The tuffs and pillow-lavas oi the Oamarn dis- 

 trict formed at this time (Park 1918, Uttley 1918, 19^0) 

 and perhaps also the basic rocks of the Moeraki Peninsula, which 

 have not yet been described in detail. In the Coromandel Penin- 

 sula, the Geological Survey of which has been completed during 

 the last decade, there occurred three phases of vulcanicity in this 

 period ; and it is to the propylitisation of the rocks of the first of 

 these that we owe the rich auriferous deposits of that region. The 

 latest bulletin on this area gives a very valuable summary by 

 Henderscn and Bartrum (1913) of the previous investigations of 

 the whole district. (See also Eell and Eraser 1912.) Later 

 Tertiary igneous activity is indicated by the extent of volcanic 

 rocks in the North Auckland Peninsula, where the invf-stigations 

 of Bell and Clarke ('1909) are new being extended by Eerrar and 

 Bartrum. It is also shown by the tuffaceous character of the 

 Upper Tertiary beds of the Gisborne, Napier, and Taranaki dis- 

 tricts, which is especially marked in the later "Pliocene" beds, 



* For fuller consideration of the problem of the Antarctic connexions reference 

 should be made to the summaries of the biological evidence by Ortmann (l'>02^, Benham 

 (1904). Hutton (1904), Chilton (HO"), Oshorn (1910), and Hedley (1912K and for 

 opposing views Cheeseman (1S09), and Matthew (1914). The geological evidence has been 

 Summarized by David (1914). 



