288 SPOLIA ZEYLANICA. 
The families may be differentiated as follows :— 
A.—Tail rounded ; bill long, flattened, and provided under- 
neath with an enormous pouch. 
Pelecanide (Pelicans). 
B.—Tail forked ; the web between the toes deeply scalloped ; 
bill straight and sharply hooked at the tip. 
Fregatide (Frigate Birds). 
C.—Tail rounded, the feathers very stiff ; bill slender, either 
hooked or pointed ; plumage mainly black. 
Phalacrocoracide (Cormorants and Darters). 
D.—Tail long and wedge-shaped ; bill stout and pointed ; 
nostrils almost invisible externally. 
Sulide (Gannets). 
E.—Tail long, the central feathers greatly exceeding the 
rest ; bill stout and pointed, the nostrils plainly 
visible. 
Phaethontide (Tropic Birds). 
Family PELECANID 2. 
Genus Pelecanus. 
Pelicans. 
The Pelicans are a familiar group of large birds with 
enormous bills, which are adapted for fishing. The upper 
mandible is very long and flattened, and terminates in a strong 
“dertrum,” or nail, at the tip. At each side, running down 
the length of the bill, there is a narrow groove from the 
nostrils, which are very small and placed at the base. The 
lower mandible is a mere flexible pointed arch forming a rim 
to the large pouch of naked skin, which is used as a net to 
scoop up fish. The wings are long and ample. Pelicans are 
found in warm climates all round the world, frequenting 
marshes, rivers, lagoons, or sometimes the sea. They can 
both fly and swim well, but do not dive, and are bad walkers, 
not often seen on land. Only one species is found in Ceylon. 
