1887.] PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 81 



Himantopus knudseul, s^i. n. 

 Knudsen's Stilt. Aeo. 



Diagnosis. — Similar to Himantojms mexicanus (Mull.), from North 

 America, but with the bhick of the head extendiug further down on the 

 forehead and occupying the proximal half of the lores 5 black on neck 

 extending to the sides and the front of the neck, except the middle line, 

 mottled with black, the feathers being narrowly tipped with black; 

 tail-feathers broadly and abruptly tipped with greenish black, nearly 

 the entire outer web of the outer pair being of the same color; tail- 

 feathers, with the outer webs, light smoky gray, and the inner ones 

 white, except the middle pair which has both webs light smoky gray; 

 bill, tarsus, and tail considerably longer than in K. mexicanus. 



Dimensio7is of type specimen. — Wing, 232™"^ ; tail-feathers, ST'"'" ; ex- 

 posed culmen, TS""""; tarsus, 121™""; middle toe, with claw, 47'"'". 



Habitat. — Hawaiian Islands. 



Type.— TJ. S. Nat. Mus., No. 110024; Kauai, Hawaiian Islands. Val- 

 demar Knudsen, coll. 



S'V'NOXYMY. 



1&7-S.— Himantopus mgricollisf Pelzeln, Verli. Zool.-Bot. Ges. Wien, 1873, p. — , Estr. 



p. 7 {nee ViEiLL.). 

 1879. — Himantojms Candidas Dole, Hawaiiau Almanac, 1879, p. 52 (nee BONX.). — 



FiNSCH, Ibis, 1880, p. 79. 



This species is most nearly related to the two American species, H. 

 brasiliensis and H mexicanus, and differs from the last one in about the 

 same degree as do the species mentioned inter se, H. mexicanus being 

 in a measure intermediate as far as the relative amount of black and 

 white in the coloration of the plumage is concerned. 



R. l-mi(1seni, which I take great pleasure of naming in honor of Mr. 

 Valdemar Knudsen who made the interesting collections upon which 

 the present paper is based, needs only comparison with S. mexicaiius, 

 and the most salient differences have already been pointed out in the 

 diagnosis. I may add that I have before me 17 specimens of the latter 

 species, representiog very fairly the individual and seasonal variation, 

 as well as that due to age and sex. The type of H. knudseni is evidently 

 an old male. 



The accompanying cuts (see Plate VI) explain at a glance the different 

 dist;?ibutiou of black and white in the two species, and make a more de- 

 tailed comparison superfluous. Suffice it to say, that in the whole series 

 of R. mexicanus, I have not found a single individual that even ap- 

 proaches H. Icmidseni, and \u none of them, old or young, is the black 

 mottlings on the fore neck even indicated, the border-line between the 

 black of the hind neck and the white of the sides being quite abrupt. 



The coloration of the tail is very peculiar, as already described in the 



diagnosis. Only in a single specimen of R. mexicanus (Xo. 84669, from 



Florida) is there any approach to the pattern exhibited by the type of 



R. Icnudseni, but the dusky markings are not so large, nor so dark and 



Proc. N. M. 87 6 



