president's address — SECTION D. 123 



ill Northern Australia. There would certainly be little 

 difficulty in regarding the present as the relic of a once more 

 universal distribution and as due to migration from some 

 northern centre. At the same time it is quite j^ossible that, 

 as Beddard suggests, Acanthodrilus may be a New Zealand 

 genus and its representatives in other southern parts be due 

 to migration southwards (though not by means of a con- 

 tinuous Antarctic continent), whilst the North Australian 

 species are the result of a small northern migration. At all 

 events a southern Pacific continent would not help much in 

 explaining the curious distribution of this typical New 

 Zealand genus. 



Tempting though it may be to accept Professor Hutton's 

 theory it appears to me as if we were scarcely justified in 

 doing so. It has rather the appearance of calling in the aid 

 of a large cause to explain a relatively small result. 



The differences between S. America and Australasia very 

 far outweigh any resemblances, remarkable though some of 

 these are, in amphibia, land mollusca, and insecta, whilst in 

 reptiles, birds, and mammals, there is no affinity worth 

 mentioning when compared with the striking contrasts 

 between the two regions, and such affinity as there is may be 

 explained quite otherwise. 



The lack of affinity with S. Africa is not conclusive 

 evidence against a southern migration from northern sources 

 and may be due to two causes, either the extinction of 

 forms, as in the case of early metatheria (or form closely 

 allied to these), or the isolation of Africa during the migra- 

 tion of forms from a Eurasian continent. 



It may be pointed out that we know of certain allied 

 forms in Australasia and S. America where the distribution 

 is most evidently a remnant of an ancient, much wider one, 

 as in the case of the Dipnoi. Though their distribution is as 

 remarkable as that of any insect or molluscan form indicating 

 alliance between S. America and Australasia still there is no 

 need to explain it by means of a S. Pacific continent. 



If, again. New Zealand were closely connected with the 

 latter it would be somewhat difficult to explain its extreme 

 poverty in such insects as the Buprestidae in which Eastern 

 Australia shows a marked affinity with S. America. At the 

 same time the distribution of this family is very difficult 

 indeed to account for owing to the affinities of the Australian 

 region with the Neotropical and Oriental on the one hand 

 and the marked distinction between the Neotropical and 



