SALANGANE SWALLOW. 537 



their powers of flight are greater and their speed more sustained ; 

 their claws are more robust and hooked. 



The principal species we have already named. It is only neces- 

 sary to mention the Clifi" Swallow (Fig. 241), the Chimney Martin, 

 the Bank Martin, and the Alpine Swift {^Cypselus alpinus), 

 Fig. 242. 



Among the foreign species the Salangane Swallow (Fig. 243) 



riff. 



212.— The Alpine Swilt i^Ci/ pscLus melha, Wood). 



may be mentioned, so famous over the world for its edible nest. 

 This bird inhabits the rocks and caverns of the sea-shore in 

 Sumatra and Java. When building it eats of the plant called 

 fucus, which abounds in these regions ; this is metamorphosed in 

 the bird's stomach, and afterwards disgorged, to fabricate the 

 walls of its nest. The fucus thus devoured forms the nutritive 

 substance so eagerly sought after by the Eastern gourmet. The 



