Io8 Allen, Origin and Distribution of N. A. Birds. [April 



other genera, Grus is common to the whole northern hemisphere ; 

 Rallus and Porza?ia are almost cosmopolitan, as are likewise 

 Gallinula and Fulica, leaving only lonornis as peculiar. This, 

 however, is tropical American rather than North American, and 

 has closely allied forms in the Old World tropics. The group is 

 thus not only widely dispersed but of known great antiquity, the 

 fossil remains of Grtis, Rallus and Fulica having been found in 

 the Eocene and Miocene deposits of Europe and in the Pliocene 

 of North Amei-ica. 



The six families of the Limicola? also afford very few peculiar 

 North American genera, and these occur where, at first thought, 

 they would be least expected, namely, among the Snipes and 

 Sandpipers. Of the Phalaropes Steganopus, a subgenus of 

 Phalaropus, is exclusively North American and the most 

 southern in distribution of the three known species of the group, 

 the others being both arctic and circumboreal. It is also of interest 

 to note that, according to Dr. Shufeldt, its remains occur in the 

 Post-Pliocene deposits of southeastern Oregon, rendering it 

 certain that North America was within the pre-glacial range of 

 the group. 



The Stilts and Avocets, on the other hand, are of nearly world- 

 wide distribution, being absent from only the cold temperate and 

 arctic portions of the globe. The same is true also of the Oyster- 

 catchers. The Surf-bird, genus Aphriza, is an isolated type of 

 extended range on the Pacific coast of both North and South 

 America during migration ; its breeding haunts have as yet 

 escaped discovery. 



The two remaining families are the Scolopacidas and the Char- 

 adriidas. Of the former fifteen genera are represented in North 

 America. One only, Gallinago, may be termed cosmopolitan. 

 Of the other fourteen, six are circumpolar, and eight are distinc- 

 tively North American, the North American genera being Philo- 

 Ziela, Afacror/iawp/tus, Aficropalama, Ereimetes, Symphemia, 

 Bartramia and Tryngites. Three of them breed from the cold 

 temperate southward. Three of them are also restricted to 

 eastern North America, while the other two — Ereunetes and 

 Macrorhamphus, both monotypic — have each developed an 

 eastern and a western subspecies. Heteractitis has a represen- 

 tative in Alaska and another in Eastern Siberia. Of the two 

 genera of Charadriidae, one, Charadrius, is arctic and circum- 

 boreal; the other, ^lEg/alitis, is cosmopolitan. 



