364 
GEOGRAPHICAL ZOOLOGY. 
[part IV. 
cosmopolitan; Ckaulelasmus (2 sp.), Palsearctic region and North 
America; Spatula (5 sp.), all Temperate regions; Malacorkynchus 
(1 sp.), Australia ; Cairina (1 sp.), Tropical South America ; 
Branta (1 sp.), Palsearctic region and India ; Fuligula (5 sp.), 
North Temperate regions and New Zealand; JEthya (5 sp.), 
Palsearctic and Nearctic regions, India, Australia, and South 
Africa ; Metopiana (1 sp.), South Temperate America ; Bucephala 
(4 sp.), Nearctic and Palsearctic regions ; Harelda (2 sp.), North- 
ern Palseartic and Nearctic regions ; Hymenolaimus (1 sp.), New 
Zealand ; Camptolaimus (1 sp.). North-east of North America ; 
Micropterus (1 sp.), Temperate Soutli America ; Somateria (5 
sp.), Arctic and sub-arctic regions ; (Edemia (5 sp.), Nearctic 
and Palsearctic regions; Biziura (1 sp.), Australia; Thalassornis 
(1 sp.), South Africa ; Erismatura (6 sp.), all America, South- 
east Europe and South Africa ; Nesonetta (1 sp.), Auckland 
Islands ; Merganetta (3 sp.), Andes of Columbia to Chili; Mer- 
gus (6 sp.), Palsearctic and Nearctic regions, Brazil, and the 
Auckland Islands. 
Family 119.— LAKTCLE. (13 Genera, 132 Species.) 
General Distribution. 
Neotropical 
SUB-REGIONS. 
N EARCTIC 
SUB-REGIONS. 
Palsearctic 
Sub-regions. 
Ethiopian 
Sub-regions. 
Oriental 
Sub-regions. 
Australian 
Sub-regions. 
1 . 2 . 3 . 4 
1 . 2 . 3 . 4 
1 . 2 . 3 .4 
1 . 2 . 3.4 
1 . 2 . 3. 4 
1 . 2.3 .4 
The Laridse, or Gulls and Terns, are true cosmopolites, in- 
habiting the shores and islands of every zone ; and most of the 
genera have also a wide range. They are therefore of little use 
in the study of geographical distribution. The genera are as 
follows : — 
Stercorarius (6 sp.), cosmopolitan, most abundant in cold and 
temperate zones; Rhodostethia (1 sp), North America; Larus 
(60 sp.), cosmopolitan ; Xema (1 sp.), North Temperate zone ; 
Creagrus (1 sp.), North Pacific ; Pagophila (1 sp.), Arctic seas ; 
Rissa (3 sp.), Arctic and Northern seas; Sterna (36 sp.), cos- 
mopolitan ; Hydrochelidon (12 sp.), Tropical and Temperate zones; 
