GLACIAL EPOCHS AND I'OLAR CLLUATES. 49 



Migration may in many cases indicate the direction 

 of past Emigration, so may the present centres of 

 Emigration denote ancient paths of Migration. 

 More ancient evidence still of species stranded 

 during Inter-Polar Migration may be found among 

 the Chioniu.e and the Thixocoriixi:, composed of 

 aberrant species of Charadrhd.*:, isolated on various 

 parts of the borders of the Antarctic Ocean. 



Mr. Seebohm has very elaborately sought to 

 show that the Charadriid.^ is a North Polar group 

 of birds, and seeks to explain the presence of some 

 of these undoubted ancient forms as due to an 

 exodus from the Arctic regions during glacial dis- 

 turbance ; but these isolated species seem to me 

 to indicate South Polar origin ; for it is only natural 

 to expect to find the least changed ancestral forms 

 nearest to the centre of dispersal, and this we cer- 

 tainly do not find in the northern hemisphere. Just 

 as the Arctic Alcid/E have their more ancient proto- 

 types, the Antarctic Impennes, indicating a remote 

 Inter-Polar Emigration, so it appears to me the 

 birds forming the groups Chionid.e and Thino- 

 coRiD/E indicate a South Polar dispersal of the 

 Charadriid.e, and a less remote Inter-Polar Migra- 

 tion. There is other evidence to show that many 

 Charadriinae birds are decidedly more Antarctic 

 than Arctic in their dispersal — not northern species 

 at all, but eminently southern, such as the Stilts 

 {Him ant opus), the Oystercatchers {Hcrmatopus), and 

 the Lapwings {J^anellus). 



The same ornithologist's Glacial Theory of Dis- 



