PROCEEDINGS OF UNITED STATES NATIONAL MUSLUM. 167 



dius* ami Hydraleclor.i 1 ain iiuable to state in just what essential 

 parlicniars the two latter difler from Parra, never having seen speci- 

 mens of any species of either form. The first, however, differs very 

 widely in the great development of the rectrices, ot which the inter- 

 media? are excessively elongated ; in the curious attenuation of the 

 primaries, which are, moreover, of very unequal length, and in the entire 

 absence of lobes about the base of the bill. These characters I have 

 drawn from figures of the single species, H. chirurgus (Scopoli), not hav- 

 ing seen the bird itself. 



In addition to the generic characters given above, the following also 

 may be mentioned: — 



Bill somewhat Plover-like in form, the basal half with the upper and 

 lower outlines nearly parallel and decidedly appr#ximated, the terminal 

 half of the culmeu strongly convex, the gouys nearly straight, and 

 decidedly ascending terminally ; nostrils small, horizontal, elliptical, 

 situated about half-way between the anterior angle of the eye and the 

 tip of the bill. Primaries 10, reaching to the tips of the tertials, the 

 three onter quills longest and nearly equal, their inner webs slightly 

 narrowed near the end. Tarsus and bare portion of the tibia covered 

 by a continuous frontal and posterior series of transverse scutelloe, these 

 sometimes fused into continuous sheaths; middle toe (exclusive of its 

 claw) about equal to the tarsus (sometimes a little shorter) ; outer toe 

 equal to the middle toe, but its claw a little shorter; inner toe a little 

 shorter than the outer, but its claw considerably longer; hallux about 

 equal to the basal phalanx of the middle toe, but its claw reaching nearly, 

 if not quite, to the end of the middle toe. 



211. Parra gymnostoma. 



Parra gymnostoma, Wagler, Isis, 1831, 517— SCL., P. Z. S. 1856,283 (S. Mexico 

 to New Granada, Diagnosis and synonymy) ; 1857, 206 (Jalapa). — 

 ScL. & Salv., Ibis, 1859, 231 (Belize, Honduras; Peten, Guatemala) ; 

 Nom. Neotr. 1873, 142.— Taylor, Ibis, 1860, 315 (Honduras).— Salvin, 

 Ibis, 1870, 116 (Costa Rica); P. Z. S. 1870, 218 (Costa Rica).— Lawr., 

 Mem. Boston Soc. II, 1874, 312 (Mazatlan, Manzauillo Bay, ZacatulaR., 

 and Rio de Coahuyana, W. Mexico. Habits. Descr. nest and eggs) ; 

 Bull. U. S. Nat. Mus. No. 4, 1876, 50 (Isth. Tehuantepec).— Merrill, 

 Bull. Nutt. Orn. Club, I, Nov. 1876, 88 (Ft. Brown, Texas ; 1 pair; 

 August). 



Parra cordifera, Less., Rev. Zool. 1842, 135 (Acapulco. Descr. adult). — Des 

 MURS, Icon. Orn. 1845, pi. 42. 



Sp. CB..— Adult: Wing, 4.50-5.40; cnlmen, 1.15-1.40 ; tarsus, 1.90- 

 2.35; middle toe, 1.85-2. 25.| Head, neck, jugulum, and extreme^ an- 

 terior portion of the back uniform black, with a iaint silky glossy-green 

 gloss below. Rest of the plumage mainly unifotm rich purplish chest- 

 nut, with a faint purple gloss, brightest or most rufescent on the wings, 



* " Metojjodius, Wagler, 1832." Type, Parra africana, Lsith., fide Gray, 

 t " Hydralector, Wagler, 1832." Type, Parra cristata, Vieill., fide Gray, 

 t Extremes of thirteen examples. 



