chap, xvni.] 
BIRDS. 
307 
The Grebes are universally distributed. The genera are 
Podiceps (26 sp.), cosmopolitau ; and Podilymbas (2 sp.), confined 
to North and South America. Some ornithologists group these 
birds with the Colymbidas. 
Family 125. — ALCFDiE. (7 Genera, 28 Species.) 
General Distribution. 
Neotropical 
Sub-regions, 
| N EA.RCTIC 
Sub-regions. 
PA L^E ARCTIC 
Sub-regions. 
Ethiopian 
Sub-regions. 
Oriental 
Sub-regions. 
Australian 
Sub-regions. 
— 
I 4 
1-3.4 ! 
— 
— 
— 
The Aleidae, comprising the Auks, Guillemots, and Puffins, 
are confined to the North Temperate and Arctic regions, where 
they represent the Penguins of the Antarctic lands. One of 
the most remarkable of these birds, the Great Auk, formerly 
abundant in the North Atlantic, is now extinct. The genera are 
as follows : — 
Alca (2 sp.), North Atlantic and Arctic seas ; Fratercula (4 
sp.), Arctic and North Temperate zones ; Ceratorhina ( 2 sp.), 
North Pacific; Simorhynchus (8 sp.), North Pacific; Braehy- 
rhamphus (3 sp.), North Pacific to Japan and Lower California; 
Uria (8 sp.), Arctic and North Temperate zones; Mergulus (1 
sp.), North Atlantic and Arctic Seas. The last three genera 
constitute the family Uriidse, of some ornithologists. 
General Remarks on the Distribution of the Anseres. 
The Anseres, or Swimmers, being truly aquatic birds, possess, 
as might be expected, a large number of cosmopolitan families 
and genera. No less than 5 out of the 8 families have a world- 
wide distribution, and the others are characteristic either of the 
North or the South Temperate zones. Hence arises a pecu- 
liarity of distribution to be found in no other order of birds ; 
the Temperate being richer than the Tropical regions. The Ne- 
arctic and Pakearctic regions each have seven families of Anseres, 
two of which, the Colymbidas and Alcidse, are peculiar to them. 
The Ethiopian, Australian, and Neotropical regions, which all 
