436 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 



of which is pecuUar to Austraha. America possesses two genera 

 and four species, each continent having a pecuMar species of each 

 genus. 



KEY TO THE GENERA OF RECURVIROSTRID^. 



a. Anterior toes all extensively webbed ; bill much depressed distally, nearly to 

 quite as long as tarsus. 

 b. Bill more or less strongly recurved; hallux present (but very small). 



Kecurvirostra (p. 436). 



bb. Bill straight; hallux absent Cladorhynchus (extralimital).o 



aa. Anterior toes cleft nearly to base; bill terete or slightly compressed distally, much 

 shorter than tarsus. (Hallux absent. ) Himantopus (p. 441). 



Genus RECURVIROSTRA Linnaeus. 



Recurvirostra Linn^us, Syst. Nat., ed. 10, i, 1758, 151. (Type, by monotypy, 



Recurvirostra avosetta Linnaeus.) 

 Avocetta Brisson, Orn., vi, 17G0, 538. (Type, " Avocetta" = Recurvirostra avosetta 



Linnaeus.) 



Large Recurvirostridse (wing more than 200 mm.) with the long, 

 slender, depressed and distinctly recurved bill nearly as long as 

 tarsus, the latter covered, all round, by small, mostly longitudinal, 

 hexagonal scales ; anterior toes extensively webbed, and hallux present 

 (though very small). 



Bill nearly to quite as long as tarsus, slender, depressed distally, 

 more or less strongly recurved for terminal half, the tip of maxilla 

 attenuated and decurved; nostril sub-basal, longitudinal, in lower 

 part of a distinct lateral groove extending for about one-third to one- 

 half the length of the maxilla. Neck rather long. Wing long and 

 pointed, the longest primary (outermost, two outermost, or, rarely, 

 second from outside) extending considerably beyond tips of elongated 

 tertials. Tail, between one-third and one-half as long as wing, 

 truncate; rectrices 12-14. Tarsus one-third as long as wing or 

 longer, compressed, covered all round with small, mostly longitudinal, 

 hexagonal scales, these larger and more longitudinal in front, smaller 

 laterally; middle toe decidedly less than half as long as tarsus, the 

 lateral toes shorter, the inner toe shorter than the outer; hallux 

 minute, but with a distinct claw; anterior toes webbed, more exten- 

 sively between outer and middle toes; bare portion of tibia one- 

 third (R. andina) to half (R. americana) as long as tarsus, the lower 

 portion scaled, like tarsus, the upper portion smooth or with scales 

 indistinct. 



. O' Lejitorhynchus (not Leptorrhynchus Guerin, 1830) DuBus, Mag. de Zool., v, 1835, 

 pi. 45 (type, L. pectorulis DuBus). Cladorhynchus Gray, List Gen. Birds, 1840, G9; 

 Gen. Birda, iii, 1849, 577, pi. 155, fig. 1 (type, Leplorhyiichus pectoralis DuBus). 



This genus is intermediate between Recurvirostra and Himantopus, though nearer 

 to the former. The single species is peculiar to Australia. 



