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Genus HYDROCHELIDON. 



Sterna apud Brisson, Orn. vi. p. 211 (1760). 



Larus apud Scopoli, Ann. I. Hist. Nat. no. 108 (1769). 



Hydrochelidon, Boie, Isis, 1822, p. 563. 



Anous apud Stephens in Shaw's Gen. Zool. xiii. pt. 1, p. 142 (1825). 



Viralva apud Stephens, torn. cit. p. 167 (1825). 



Pelodes apud Kaup, Natiirl. Syst. p. 107 (1829). 



Gelichelidon apud Gray, Hand-1. of B. iii. p. 119 (1871). 



Although closely allied to the genus Sterna, the Marsh-Terns differ in having a short tail, long 

 slender toes connected by deeply incised webs, as well as in general coloration. This genus is 

 represented in the Palsearctic, Ethiopian, Oriental, Australian, Nearctic, and Neotropical Regions, 

 three species being resident in the Western Palsearctic Region. They are tame and confiding, 

 in their flight and general movements closely resembling the common Terns ; but they frequent 

 inland marshy localities more than the sea-coast. They breed in large marshes, making a 

 tolerably well-constructed nest of grass and marsh-plants, in which they deposit three eggs, 

 ochreous-clay or olivaceous-ochreous in colour, closely blotched and spotted with purplish grey 

 and blackish brown. 



Hydrochelidon nigra, the type of the genus, has the bill about as long as the head, nearly 

 straight, tapering to a fine point, nasal groove rather long, the nostrils basal, direct, oblong; 

 wings long and pointed, the first quill longest ; tail rather short, much shorter than the closed 

 wings, tolerably deeply forked ; feet short, the tibia bare for a considerable distance ; tarsus 

 short, compressed, anteriorly scutellate ; hind toe small ; anterior toes slender, connected by 

 deeply emarginate webs which scarcely reach beyond the centre of the toe ; claws long, slender, 

 moderately curved, rather obtuse. 



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