354 PROCEEDINGS OF SECTION D. 



further radiant energy of any appreciable intensity. Such areas 

 are found in deserts with the deposits of silicates (Si., at.wt. 28-2,) 

 and here life is practically non-existant. 



In this paper, although the possible changes have been rapidly 

 noted, the production of any modification and the formation of a 

 characteristic is not assumed to be rapid and apparent, but took 

 thousands of years to produce, and the words of Fk. Soddy, that 

 " only those changes which require an aeon for completion remain 

 with us still," can be aptly extended to the past as well as to the 

 present. 



To conclude, I have only been able to briefly suggest the 

 possibilities of the hypothesis, as many of the propositions noted 

 are capable of expansion into a paper by themselves, and this paper 

 would have been too evtensive. I have been unable to touch on 

 the evolution of the floral kingdom for similar reasons, although it 

 admits many interesting theories. Finally, I hope this hypothesis, 

 even in this condensed form, will meet with favourable considera. 

 tion, which I think it merits. 



14._SOME EFFECTS OF THE GASES EdSSOLVED IN ARTESIAN 

 WATER ON TROUT, THEIR EGGS AND FRY. 



By C. COLERIDGE FARR, D.Sc, Professor of Physics in the Canterbury College, Christchurch, 



New Zealand. 



Some eighteen months ago the council of the Canterbury Philo- 

 sophical Institute set up a committee to examine and report upon 

 the various problems presented by the artesian water system of 

 Christchurch. One of the questions which suggested itself was 

 an examination of the water for radio-active constituents, and it 

 feU to the author and his assistant, Mr. D. C. Florance, M.A., M.Sc, 

 and Mr. D. B. McLeod, M.A., to undertake the work. The facts 

 which have come to light, though possibly having no connection 

 with radio-activity, are the outcome of the investigation, and it 

 is thus that the author finds himself in the somewhat curious 

 position of presenting a paper for the consideration of biologists, 

 a task which he enters upon with considerable trepidation. 



The Canterbury artesian water system is extensive, and as 

 far as dissolved salts are concerned extremely pure, so pure indeed 

 that it is used for many chemical purposes for which distilled water 

 is generally considered necessary. A typical analysis illustrated 

 this. It is obtained by simply driving pipes through the bed of 

 shingle and sand, and the whole deposit of which the Canterbury 

 plains are built up to depths which range from about 80 feet to 

 800 feet. The deeper the penetration of the pipe, the more 

 copious the flow and the greater also its surface head. These 

 artesian weUs are extremely abundant about Christchurch, one, or 

 somewhere perhaps two, being found on any section upon which 

 a house has been built. 



