STRUTHIOUS BIRDS. 367 



further, in the moas, by the expanded sacrum and the less 

 obtuse coraco-scapular angle in the smaller species. 



Again, the only small Ratitce are found in New Zealand, 

 and if the group is descended from flying birds the smaller 

 forms must have jjreceded the larger ones. We should 

 expect to find the least altered forms near the place of 

 origin, and if the New Zealand Ratitw have migrated from 

 Europe or Asia how comes it that all the least modified 

 forms have been collected together in those islands ? Fligiit- 

 less birds have generally been developed on lands where 

 there are no carnivorous mammalia, and not on the large 

 continents of the Northern Hemisphere. 



There would be no great difficulty in accounting for a migra- 

 tion by land of these birds into Australia from New Zealand, 

 while a counter migration of Austrahan mammals was 

 ]>revented. At some former period, when New Zealand 

 stretched towards Northern Austraha, a portion of land, pro- 

 l)ably including Norfolk Island, and inhabited by Ratitcp., 

 may have been detached from New Zealand and subsequently 

 united to Austraha, when the Ratitce would spread into the 

 mainland. 



Mr. H. O. Forbes, in a paper read to the Philosophical 

 Institute of Canterbury, N.Z., a summary of which was pub- 

 lished in the daily press of the 22nd October last, has formed 

 a new genus, called Palcpo-casuarius, for the reception of 

 three species founded on tibice presenting " many casuarine 

 characters " ; and if this determination is confirmed it will 

 be a distinct proof that the cassowaries originated in New 

 Zealand. It is, however, remarkable that so old a form as 

 Palceo-casuarias must be should be still in existence in the 

 Pleistocene period. 



What, now, Avere the flying ancestors of the Australasian 

 Ratitce^ The Tinamous of Central and South America 

 resemble the New Zealand Ratitce in several particulars, not 

 only in the structure of the skull, but in the free ischia and . 

 pubes, in the presence of a free post-axial tarsal bone, and in 

 the absence of tail feathers. As a former connection be- 

 tween New Zealand and South America is shown bv the 

 ])lants, the frogs, and the land shells, it seems more probable 

 that the Struthious birds of Australasia originated in the 

 neighbourhood of New Zealand from flying birds related to 

 the Tinamous, and that they sjiread fi-om thence into Aus- 

 tralia and New Guinea, rather tlian that they should have 

 migrated southwards from Asia. If this supposition is a 



