166 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 



Family PARRHLE: The Jacanas. 



Parridce, "Selys, 1842".— Gray, Hand-list, HI, 1871, G9.— Scl. & Salv., Norn. Neotr. 

 1873, viii, 142.— Boucard, Cat. Av. 1876, IX, 11. 



< Pallida, Vigors (fide Gray).— Lilljeborg, P. Z. S. 1866, 17. 



= Parrinw, Gray, List Genera B. 1840, — ; 2d ed. 1841, 91 ( < Palamedeida).— Gray & 

 Mitch., Genera B. 4to, III, 1849, 588 ( < Palamedeida') ; Genera and Subg. 1855, 

 119 ( < Palamedeida?).— Lilljeborg, P. Z. S. 1866, 17 ( < Pallida). 



< Palamedeida?, Gray, I. c. 



< Gallinulidce, Blas. (fide Gray). 



Ch. — Small-sized wading birds, combiniDg the general appearance of 

 Eails and Plovers, but differing from either in the remarkable and ex- 

 cessive elongation of the toes and claws, the latter nearly straight and 

 much compressed, that of the hallux much longer than its digit and 

 slightly recurved. 



The above brief diagnosis is sufficient to distinguish the Jacanas from 

 all other wading birds. Their nearest allies appear to be the Plovers, 

 from which they differ chiefly in the character of the feet, as pointed 

 out above. The single American genus Parra, Lath., is further charac- 

 terized by the presence of leaf-like lobes at the base of the bill, and a 

 sharp, conical spur projecting from the inside of the bend of the wing, 

 in the possession of which features they present a striking analogy to 

 certain Plovers, as the genera LobiraneUus, Strickl., and Eojrfopterus, 

 Bonap. The genus 7 V nv/, of which there are several species, all Ameri- 

 can,* is characterized as follows: — 



Genus PARRA, LinosBOS. 



< Jacana, Biuss., Orn. V, 1760, 121. Type, Parra jacana, Auct. (Ineludes Hydralector, 



Wagl., and Mclopodius, Wagl.) 



< Gallinula, Ray (fide Gray). 



< Parra, Linn., S. N. I, 1766, 259. Type, P. dominica, Linn.,= LobiraneUus brissoni, 



(Wagl.) ! (Includes also Chauna and Jacana.)— Latham, Ind. Orn. II, 1790, 762. 

 Type, P. jacana, Linn. (Includes Jlydrophasianns, Wagl., Chauna, Illiger, and 

 Metopodius, Wagl.)— Gray, Hand-list, III, 1871, 69 (subg. Parra). 

 = Parra, Gray, List Genera, 2d ed. 1841, 91 ; Gen. and Subg. 1855, 119, No. 1976.— 

 Gray & Mitch., Genera B. Ill, 1849, 288.— Scl., P. Z. S. 1856,282 (synopsis of 

 species).— Scl. &. Salv., Norn. Neotr. 1873, 142 (list of species).— Boucard, Cat. 

 Av. 1876, 11 (list of species). 



Ch. — Reiniges normal. Rectrices much abbreviated, very soft, entirely 

 concealed by the tail-coverts. Forehead with large, leaf-like lobe, free 

 laterally and posteriorly, adhering centrally and anteriorly; rictus orna- 

 mented by a smaller lobe (rudimentary in P. gymnostoma). 



The above characters are chiefly those which distinguish the Ameri- 

 can genus Parra from its Old World allies HydrophasianwJ Metopo- 



* For a synopsis of the species of this genus, see Sclater " On the American Genus 

 Parra ", in Proc. Zool. Soc. Lond. 1856, p. 282. 



t" Hydrophaaianus, Wagler, 1832." Type, LT. chirurgus (Scopoli). 



