420 Transactions. 



reasonable, therefore, to attribute the humid climate either to causes which 

 have affected the earth as a whole or to altered meteorological conditions 

 promoted by some change in the distribution of land and water in the 

 Southern Hemisphere. 



Conclusion. 



The general sequence of events since the glaciation of the South Island 

 in Pleistocene and post-Pleistocene times appears to have been the fol- 

 lowing : — 



(1.) Glacial conditions, with probable steppe chmate existing contem- 

 poraneously on the land to the east of the terminations of the glaciers, a 

 condition which probably continued for some time, as the glaciers were 

 retreating. 



(2.) Moist climate over the tract to the east of the main range, during 

 which the forests were estabhshed or were widely spread and the rivers 

 built up their fans. 



(3.) Modified steppe conditions over the belt to the east of main range. 



The conclusions are, in general, similar to those which have been agreed 

 upon by European geologists as occurring in Europe, although an important 

 school has demanded the existence of a succession of warmer and milder 

 conditions. Of course, it is impossible at present to make any inference 

 as to such a succession of milder and more severe climates in New Zealand, 

 or even to infer that the changes in climate suggested by the various lines 

 of evidence indicated above were contemporaneous. Some of the changes 

 suggested may be due to causes which operated in Tertiary times. How- 

 ever, in view of the general interest in the matter, the author hopes, in 

 spite of obvious deficiencies in the statement of the case, that this paper may 

 serve to draw attention to a problem which has an important bearing on 

 the climate of the world as a whole, and also on the evolution of the vege- 

 tation and the plant-associations which exist at present in this country. 



Art. XL,— ^ Preliminary Account of the Geological Features of the Christ- 

 church Artesian Area. 



By R. Speight, M.A., M.Sc, F.G.S. 



[Bead before the Philosophical Institute of Canterbury, 7th December, 1910.] 



Plates IX-XIV. 



[Note.- — ^This paper embodies the results available at present of an examination of 

 the beds of the Christchurch artesian area. Although they are necessarily imperfect, 

 it has been thought advisable by the author to submit them in this form, as they are 

 complete in some respects ; in others, they are quite imi)ei"fect, and observations ex- 

 tending over several y(^ars will have to be made before any finality in the conclusions 

 can be reached.] 



Introductory. 



The part of Canterbury stretching along the coast-line from the mouth 

 of the Waimakariri to the west of Banks Peninsula as far as the mouth of 

 the Rakaia is perhaps the most extensive area in New Zealand where plentiful 

 f-upplies of water can be obtained from artesian wells. The interest which 



