NATATORES. 447 



mud in which they habitually seek their food. The bill is 

 richly supplied with filaments of the fifth nerve, and doubtless 

 serves as an efficient organ of touch. The feet are furnished 

 with four toes, of which three are turned forwards, and are 

 webbed, whilst the fourth is turned backwards, and is free. 

 The trachea in the males is generally enlarged or twisted in 

 its lower part, and co-operates in the production of the peculiar 

 clanging note of most of these birds. The body is heavy, and 

 the wings only moderately developed. 



The groups of the Ducks (Anatida), Geese \Anserina\ 

 and Swans ( Cygnida\ are too familiar to require any special 

 notice. 



The Flamingos, however, forming the group of the Phcenicop- 

 teridce, require some notice ; if only for the fact that the legs are 

 so long and slender that they have often been placed in the 

 order Grallatores on this account. The three anterior toes, 

 however, are webbed or completely united by membrane, and 

 the bill is lamellate, so that there can be little hesitation in 

 leaving the Flamingo in its present position amongst the Nata- 

 tores. The common Flamingo (Phoznicopterns ruber) occurs 

 abundantly in various parts of southern Europe. It stands 

 between three and four feet in height, the general plumage being 

 rose-coloured, the wing-coverts red, and the quill-feathers of 

 the wings black. The tongue is fleshy, and one of the extrava- 

 gances of the Romans during the later period of the Empire 

 was to have dishes composed solely of Flamingos' tongues. 

 Other species occur in South America and Africa. 



ORDER II. GRALLATORES. The birds comprising the order 

 of the Grallatores, or Waders, for the most part frequent the 

 banks of rivers and lakes, the shores of estuaries, marshes, la- 

 goons, and shallow pools, though some of them keep almost ex- 

 clusively to dry land, preferring, however, moist and damp situa- 

 tions. In accordance with their semi-aquatic amphibious habits, 

 the Waders are distinguished by the great length of their legs ; 

 the increase in length being mainly due to the great elongation 

 of the tarso-metatarsus. The legs are also unfeathered from 

 the lower end of the tibia downwards. The toes are elongated 

 and straight (fig. 174, A), and are never completely palmate, 

 though sometimes semi-palmate. There are three anteriqr toes, 

 and usually a short hallux, but the latter may be wanting. The 

 wings are long, and the power of flight usually considerable ; 

 but the tail is short, and the long legs are stretched out behind 

 in flight to compensate for the brevity of the tail. The body 

 is generally slender, and the neck and beak usually of consid- 

 erable length (fig. 174, B). They are sometimes polygamous, 



