AND TYPES OF EGGS. 39 



Sternula, Thallasseus, Onochoprion, Anous). Terns are as a rule migra- 

 tory, and congregate in flocks during the breeding season. The 

 Caspian tern (S. caspius) does not breed in this country; and the 

 gull-billed tern (G. anglicus) only breeds in the far north-west. The 

 marsh terns (Bydrochelidori) breed here and there in India gregariously 

 on weeds floating in swamps. The true terns ( Gelochelidon, ' Sterna, 

 Seena, Sternula) lay their eggs on the bare sand in the beds of large 

 rivers. The sea terns (Thallasseus, Onochoprion, Anous) lay on bare 

 rocky islands off the sea-coast. All the terns lay handsomely^marked 

 eggs. 



Skimmers, (Rhynchops). Are permanent residents here, and are 

 similar in their eggs, habits, and distribution to the true terns (Sterna). 

 Fishers, (Phaeton, Sula, Attagen). Are all sea-birds which are 

 found in Indian waters, but which are not known to breed on our coasts. 



Pelicans, (Pelecanus). Pelicans are widely spread throughout 

 India in the cold weather, but of their breeding here nothing is known. 

 They are said to build on trees. 



Cormorants, (Graculus). Are permanent residents in India, 

 frequenting rivers and large tanks. They are gregarious and consequently 

 local breeders. The breeding of the big cormorant (G. carlo) is not 

 accurately known; and this bird is certainly to a great extent migratory. 

 The eggs of cormorants are dull chalky white. 



Snake Birds, (Plotus). Are permanent residents in India, and 

 are similar in their habits and eggs to the cormorants. 



