50 



turbinate, some wliite with green spots, some black and 

 yellow on diagonal lines, and some dull olive witb few yellow 



spots It is a remarkable fact that the larger 



shells of these species are found in Southern Tasmania, and 

 they beconle smaller, more decidedly ornamented, and highly 

 coloured as they approach the tropics." 



When we take into consideration the remarkable varia- 

 bility, under slightly different conditions, of various species 

 at the present hour, and the vast period during which such 

 changes have taken place in the facies of our Australian 

 marine fauna, as to have caused the disappearance of 92 per 

 cent, of the original tertiary species, it seems to me a difficult 

 thing to assert that Australian geology has no reasonable 

 evidence to offer in favour of evolution. To me — while 

 making every allowance for the persistency of the lower 

 forms of life, and of one or two particular types — the evi- 

 dence of Australian geology appears to be in perfect harmony 

 with the theory of evolution as represented by its best 

 exponents. 



As I understand the theory, original change of form (not 

 hereditary change) only follows material change of the con- 

 ditions affecting the immediate environment of particular 

 organisms, whether vegetable or animal. There is reason to 

 believe, therefore, that, as regards the lower organisms of the 

 ocean which survive, the external conditions affecting them 

 have not undergone any material alteration since the early 

 epoch w^hen the Trilobite peopled the depths of the ocean. Evo- 

 lution, therefore, is in perfect harmony with facts which dis- 

 close the persistency of particular tA^^es. I am also fully 

 convinced that it vrould be unscientific to look ujjon Austra- 

 lian fossil forms as in some ma.nner independent and distinct 

 from the 2)ast life of the world elsewhere. In the Avorld's 

 life-history the fossil forms of Australia are as purely colo- 

 nial (as regards completeness and origin) as the European 

 races of animals and plants which, within the last century, 

 have occupied its surface. 



It seems to me unwise to restrict our attention to the few 

 widely isolated fragments of the past life of the world, as 

 represented by Australian geology, when we take into con- 

 sideration the evolution hypothesis — which rests upon the 

 whole past changes of life on this earth of ours. 



