268 CHARADRIIFORMES 



CHAP. 



tinct P. petersi, reaching from the Lower Congo to South East 

 Africa, are larger forms, with round ochreous spots above, and red 

 feet. Heliopais jpersonata, extending from Assam to Sumatra, 

 has a black throat, orange bill, and light green feet. 



Order XI. CHARADRIIFORMES. 



The Charadriiformes are here taken to consist of five Sub-Orders. 

 Of these the Limicolae contains the Families Charadriidae (Plovers, 

 Sandpipers, Snipes, and so forth), Chionididae (Sheath-bills), Glareo- 

 lidae (Pratincoles, Coursers, and Crab-Plover), Thinocorytlvidae 

 (Seed- Snipes), Oedicnemidae (Stone -Curlews), and Farridae 

 (Jaqanas) ; the Lari possesses one Family, Laridae (Gulls, Terns, 

 and Skuas) ; the Alcae only the Alcidae (Auks) ; the Pterocles, 

 the Pterodidae (Sand-Grouse) ; but the Columbae may be divided 

 into Dididae, Didunculidae, and Columhidae. The first three may 

 again be combined into a Laro-Limicoline group, and the last two 

 into a Pteroclo-Columbine, in accordance with their affinities. 



In structure the LiMicoLAE are sufficiently uniform to be con- 

 sidered simultaneously. 



The bill furnishes a useful means of subdividing the Chara- 

 driidae. It is hardest in Haematopus, IMdorhyneJius, Strepdlas, 

 and so forth, being in them bony throughout. In Cliaradriiis, 

 Aegialitis, Zohivanellus, Vanellus, and the like, it has a hard tip, 

 but is comparatively flexible towards the base. These may com- 

 pose Sub-family (1) Charadriinae. In Totanus, and its nearest 

 allies, it is still hard at the tip, but more flexible at the base. 

 In Tringa, and similar genera, it ceases to be hard at the tip, and 

 is slightly endowed with nerves. These may constitute Sub- 

 family (2) Tringinae. In Scolopax, Gallinago, and Bhynckaea it 

 becomes highly nervous at the tip, and therein differs from that 

 of all other birds. These form Sub-family (3) Scolopacinae. In 

 Himantopus and Recurvirostra the bill is so attenuated as hardly 

 to be called hard at the tip, but it has no nerves there. The form 

 of the beak varies greatly, being asymmetrical and twisted to the 

 right in Anarhynchus, up-curved from the middle in Avocctta, 

 wedge-like in Haematopus, much flattened in Tringa platyrhyncha, 

 spade -shaped in Eurynorhynchus, arched in Numenius, and 

 strongly decurved in Ibidorhynchus. In the Chionididae a horny 

 sheath covers the base of the maxilla, and is indicated by faint 

 lines in the young ; in Glareola the bill is short, curved, and very 



