CHAP, vl] geographical AND GEOLOGICAL CHANGES. 



97 



New Zealand. In North America there are immense coal 

 fields in Nova Scotia and New Brunswick, from Pennsylvania 

 southward to Alabama, in Indiana and Illinois, and in Missouri ; 

 and there is also a true coal formation in South Brazil. This 

 wonderfully wide distribution of coal, implying, as it does, a 

 rich vegetation and extensive land areas, carries back the proof 

 of the persistence and general identity of our continents to a 

 period so remote that none of the higher animal types had 

 probably been developed. But ^ve can go even further back 

 than this, to the preceding Devonian formation, which was 

 almost certainly an inland deposit often containing remains 

 of fresh-water shells, plants, and even insects ; while Professor 

 Kamsay believes that he has found " sun-cracks and rain- 

 pittings " in the Longmynd beds of the still earlier Cambrian 

 formation.^ If now, in addition to the body of evidence here 

 adduced, we take into consideration the fresh-water deposits 

 that still remain to be discovered, and those extensive areas 

 where they have been destroyed by denudation or remain 

 deeply covered up by later marine or volcanic formations, we 

 cannot but be struck by the abounding proofs of the permanence 

 of the great features of land and sea as they now exist ; and we 

 shall see how utterly gratuitous, and how entirely opposed to all 

 the evidence at our command, are the hypothetical continents 

 bridging over the deep oceans, by the help of which it is so 

 often attempted to cut the Gordian knot presented by some 

 anomalous fact in geographical distribution. 



Oceanic Islands as Indications of the Fermanence of Continents 

 and Oceans. — Coming to the question from the other side, 

 Mr. Darwin has adduced an argument of considerable weight 

 in favour of the permanence of the great oceans. He says 

 {Origin of Species, 6th Ed. p. 288): ''Looking to existing oceans, 

 which are thrice as extensive as the land, we see them studded 

 with many islands ; but hardly one truly oceanic island (with 

 the exception of New Zealand, if this can be called a truly 

 oceanic island) is as yet known to afforl even a fragment of 

 any Palseozoic or Secondary formation. Plence we may perhaps 

 infer that during the Palaeozoic and Secondary periods neither 



1 Physical Geography and Geology of Great Britain, 5th Ed. p. 61. 



H 



