318 



SCIENCE. 



[N. S. Vol. III. No. 61. 



some of them appear to have Eatite affini- 

 ties, others present quite as strong relation- 

 ship to Carinate types. Most of them are 

 known, however, from such fragmentary re- 

 mains that little can be said as to their real 

 affinities. Indeed, it is the belief of several 

 eminent authorities that the so-called Ea- 

 titse constitute a very heterogeneous group, 

 the prominent types of which originated in- 

 dependently from perfectly distinct Cari- 

 nate ancestors. The fact of the occurrence, 

 either still living or only recently extinct, 

 of degenerate flightless forms in such widely 

 distinct Carinate groups as parrots, birds 

 of prey, pigeons, ducks and geese, coots, 

 gallinules and rails, auks, grebes, etc., and 

 that they are in general among the largest 

 members of their respective groups, and 

 also generally inhabitants of islands, shows 

 that mere Sightlessness, large size, insular 

 habitat, and an unkeeled sternum are factors 

 of slight importance. 



Mr. H. O Forbes in his plea for an Ant- 

 arctic continent ( Antipodea) originally laid 

 great stress upon his discovery at the Cliat- 

 ham Islands of an extinct flightless rail al- 

 lied to an extinct flightless rail of the genus 

 Aphanapteryx found in Madagascar. Indeed, 

 this discovery seems to have been largely 

 the foundation of his original ' tremendous 

 hypothesis,' as Mr. Wallace has called it, 

 of an Antarctic continent. In Madagascar 

 Aphanapteryx was contemporary with the 

 dodo, both existing down to about two 

 hundred years ago. The Chatham Island 

 remains were found in kitchen middens of 

 the Morioris, showing that here the sup- 

 posed Aphanapteryx existed to a compara- 

 tively recent date. Later examinations by 

 competent authority, however, of the Chat- 

 ham Island remains has shown that they 

 are not congeneric with Aphanapteryx. 



It is of interest to note in this connection 

 that some ten genera of flightless Ealline 

 birds are known, three or four of which are 

 still living, while most of the others have 



become extinct only within historic times. 

 They are all island birds, and nearly all 

 happen to occur in the southern hemi- 

 sphere, the localities being the islands of 

 Mauritius, Eodriguez, Gough, Tristan d' 

 Acunha, Samoa, Chatham, and New Zea- 

 land, but ranging north also to the Moluc- 

 cas. Furthermore, it happens that they 

 represent all of the leading types of the 

 family Eallidse, as rails, coots, gallinules 

 and porphyries, and hence have no very 

 intimate relationship. The fact of their 

 being insular forms thus has not necessarily 

 any bearing on the question of former south- 

 ern land areas, especially since thej' are as 

 much ti'opical and subtropical as austral, 

 and belong to an ancient type of bird life of 

 cosmopolitan distribution. The current be- 

 lief among ornithologists is that all these 

 forms originated at or near where they are 

 now found from ancestors that could fly. 

 In support of this belief is the fact that one 

 of the earliest marks which distinguish in- 

 sular forms from their nearest mainland 

 allies and jjrobable ancestors is the reduc- 

 tion of the wings and the corresponding in- 

 creased development of the pelvic limbs, as 

 is illustrated in the birds of the Guadalupe 

 Islands oft' the coast of Lower California, 

 and the Galapagos Islands. This change 

 is obviously the result of the new conditions 

 of life — the very limited area to which they 

 are restricted, their sedentarj^ and non- 

 migratory habits, and their comparative 

 freedom from harrassing rapacious enemies. 

 The Eatitse and supposed Ratite forms 

 which have so generally been cited in evi- 

 dence of former connected Antarctic land 

 areas, in reality afford no greater proof of 

 such land bridges than do Carinate birds, 

 when we consider how very distinct are the 

 ordinal groups into which this subclass is 

 divided, and how wldelj^ each one is sepa- 

 rated geographically from all the others. If 

 we had moas, or ostriches, or kiwis, or 

 cassowaries, or any one of the six orders 



