II.] AUSTRALIA AND NEW ZEALAND. 59 



Zealand. Finally, this hypothetical bridge sank, isolating such 

 forms as had reached New Zealand, and, soon after, Eastern and 

 Western Australia became connected by land, and thus assumed 

 a homogeneous fauna. From this and other passages, we are led 

 to conclude that the author believes that the Notogaeic flightless 

 birds immigrated, if not in Cretaceous, at least in early Tertiary 

 times 1 , from more northern regions. 



Dr Wallace's conclusions are, however, challenged by Mr C. 

 Hedley 2 , who, from a study of the floras of these regions, supple- 

 mented by the distribution of land molluscs, and recent geological 

 observations, refuses to admit that Western Australia ever pos- 

 sessed a monopoly of characteristic Australian animals or plants. 

 Although he considers the separation of the western and eastern 

 portions of the continent by a Cretaceous sea may be granted, 

 yet the land representing Western Australia was much smaller 

 than Wallace supposes. " The shallow inland Cretaceous sea was 

 studded with islands, large and small, which served the fauna and 

 flora as stepping-stones in their migrations from west to east and 

 from east to west." During a late era in the Tertiary epoch he 

 believes New Guinea to have been in connection with Australia ; 

 and further urges " that an ancient continent, separated on the 

 west from Australia by the abysses of the Coral and of the Tasman 

 Sea, is represented by the Solomons, the Fijis, the New Hebrides, 

 New Caledonia, Lord Howe Island, and New Zealand, with its 

 outlying islands In conclusion, I would contend that New 

 Zealand is associated with the Solomons and the New Hebrides, 

 firstly, as a member of their volcanic system ; secondly, by com- 

 munity of fauna and flora; whereas to Australia it is related not 

 at all physically, and to a foreign and intrusive element bio- 

 logically ; and that a theory which derives the fauna and flora of 

 New Zealand primarily from these archipelagoes and remotely 

 from New Guinea, necessitates fewer unproved assumptions than 

 that which derives them from Australia." 



To return to the ratite birds, it may be observed in the first place 



1 If the immigration into Eastern Australia was Tertiary, what becomes of 

 the author's statement that Australia has been isolated since the Secondary 

 epoch ? 



a Appendix, No. i6> 



