174 BULLETIN 133, UNITED STATES NATIONAL MUSEUM 



A young bird half-grown, collected December 8 at Zapala, has 

 most of the original covering of down rej^laced by the immature 

 plumage, though much down still persists on the head. Adult 

 males in somewhat worn plumage were taken December 8 and 9. 

 One of these had the gonys, culmen, and tip of the bill dull black; 

 remainder of maxilla deep olive buff ; remainder of mandible vetiver 

 green ; nasal operculum deep neutral gray ; iris Rood's brown ; tarsus 

 and toes chamois. A male and a female preserved as skins from 

 Concon are in full fall plumage. Specimens were preserved in 

 alcohol and as skeletons. 



The curious opercular flap that covers the nostril in the seed snipe 

 is an undoubted protection against wind and sand to a bird that 

 much of the time inhabits regions where protective cover is scant 

 and strong winds carry clouds of dust. It may be remarked that 

 the Pteroptochids Rhinocrypta and Teledromas that inhabit the 

 same areas have developed a very similar structure. 



Order COLUMBIFORMES 

 Family COLUMBIDAE 



LEPTOTILA OCHROPTERA OCHROPTERA (Pelzeln) 



Leptoptila ochroptera Pelzeln, Ornith. Brasiliens, pt. 3, January, 1870, 

 p. 278. (Sapitiba, Brazil.) 



After comparison of a fair series of pigeons of this species from 

 southern Brazil, Paraguay, and Uruguay, I am able to distinguish 

 the typical subspecies from cJilorauchenia only by size, as in the 

 series at hand color differences seem variable. Northern birds 

 usually are duller in color on the abdomen than those from the south, 

 a difference that perhaps is constant in fresh specimens, but is sub- 

 ject to variation with age, as younger individuals are duller than 

 those that are older. Specimens also discolor with time, so that those 

 taken 30 or 40 years ago are not comparable with fresh material. 

 Males of L. o. ochroptera have the wing 146 to 148.5 mm. (speci- 

 mens from Kilometer 182, Formosa, and upper Paraguay) ; females 

 135.5 to 142.5 mm. (Jaboticabel, Sao Paulo; Puerto Pinasco, Para- 

 guay; Rio Bermejo, above its mouth, Argentina). 



In Leptotila o. chlorauchenia the wing in males measures from 

 153 to 158 mm. (specimens from Rio Grande do Sul, Brazil; Laz- 

 cano, Uruguay; Las Palmas, Chaco; Conchitas, Buenos Aires); in 

 females from 150.5 to 153.3 (San Vicente, Uruguay; Las Palmas, 

 Chaco.) Specimens from Las Palmas, Chaco, near the Rio Para- 

 guay, are the southern form. Two from Kilometer 182, in the in- 

 terior of the Formosan Chaco, have the measurements of the north- 

 ern form but are intermediate in color, since one is light and the 



