PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 167 



dius,* and Hydralector A I am unable to state in just what essential 

 particulars the two latter differ 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, of which the inter- 

 mediae 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 approximated, the terminal 

 half of the culmen strongly convex, the gonys 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 outer 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 scutellae, 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) ; 

 Norn. 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,Manzanillo Bay, ZacatulaR., 

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

 Bull. U. S. Nat. Mus. No. 4, 1876, 50 (lath. 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. CH.— Adult: Wing, 4.50-5.40 ; culmen, 1.15-1.40 ; tarsus, 1.90- 

 2.35; middle toe, 1.85-2.254 Head, neck, jugulum, and extreme an- 

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

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

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



* " Metopodius, Wagler, 1832." Type, Parra africana, L&th., fide Gray, 

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

 \ Extremes of thirteen examples. 



