BIRDS OF NORTH AND MIDDLE AMERICA. 7 



bb. Frontal shield with free margins. 



c. Metacarpal spur rudimentary or small, blunt; primaries wholly blackish. 

 d. Frontal shield very large, ridged or crested medially; bill more slender, 

 not longer than head. (Australia, New Guinea, Celebes, southeastern, 



Borneo, and Philippines.) Irediparra (extralimital).a 



dd. Frontal shield small, not ridged or crested medially; bill much stouter, 

 longer than head. (India to Siam, Java, Sumatra, and Celebes.) 



Metopidius (extralimital).^ 

 cc. Metacarpal spur well-developed, sharp; primaries greenish yellow, margined 

 terminally with blackish Jacana (p. 7). 



Genus JACANA Brisson. 



Jacana Brisson, Orn., v, 1760, 121. (Type, by tautonymy, [Jacana] jacana Bris- 



son= Parra jacana Linmsus.) 

 Parra Linn.-eus, Syst. Nat., ed. 12, i, 1766, 259. (Type, P. jacana Linnseus.) 

 Asarciac Sharpe, Cat. Birds Brit. Mus., xxiv, 1896, 86. (Type, by original desig- 

 nation, Parra variabilis Linnseus=i^uh'cfl spinosa Linnaeus.) 



Rather small JacanidaB (whig 110-140 mm.) with a well-dovelopod 

 acute metacarpal spur, a conspicuous bifid or trifid frontal shield, 

 and with the primaries greenish yellow, margined termmally with 

 dusky. 



Bill about as long as or longer than head, somewhat plover-like 

 in form, the basal half with upper and lower outlines nearly parallel 

 and decidedly approximated, the terminal half enlarged (vertically) 

 through decided convexity of culmen and prominence of gonydeal 

 angle, the gonys nearly straight, ascending terminally; nostril small, 

 longitudinally^ elliptical, situated about half-way between anterior 

 angle of eye and tip of bill; nasal fossae large and relatively broad, 

 extending about to base of arched distal portion of culmen; malar 

 antia far anterior to obliquely vertical line of loral antia, the mental 

 antia extending nearly if not quite as far as anterior end of nostril; 

 rhino theca continued basally over forehead in form of a conspicuous 

 frontal shield with free margins, its posterior margin bifid or trifid; 

 rictus with a smaller pendent lobe (rudimentary or obsolete in /. 

 spinosa). Wing ample but rounded, the three outermost primaries 

 longest and nearly equal, and scarcely if at all extending beyond 

 tips of longest elongated but broad tertials; inner webs of longest 

 primaries slightly contracted terminally. Tail very short, the rec- 

 trices veiy soft, entirely concealed by coverts, 10 in number. Tarsus 

 between one-half and one-third as long as wing, compressed, con- 

 tinuously transversely scutellate before and behind, the scutella, 

 however, sometimes fused into nearly continuous plates; bare por- 



o Hydralcclor of authors (not of Wagler, Isis, 1832, 280). Irediparra Mathews, Novit. 

 Zool., xviii, 1911, 7 (tjT5e, by original designation, Parra gallinacea Temminck}. 

 (Monotyjjic.) 



^ Mciopidins Wagler, Isis, 1832, 279 (type, by subsequent designation, Parra indica 

 Latham). (Monotj'pic.) 



c"Ao-apKos, without flesh, lean. (Richmond.) 



