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SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I50 



out briefly on higher ground, they are found mainly in lower areas. 

 It is seldom that one is seen wholly in the open, and when they cross 

 trails, or other areas where there is no cover, usually they fly. On 

 floating vegetation they often run with wings flapping to keep from 

 sinking. 



As noted in the heading, some individuals have the wing coverts 

 marked with light bars that vary from white to cinnamon-brown. 

 Two distinct races are found in the Republic. 



Fig. 58. — White-throated rail, carrasqueadora, Lateralhis alhigularis. 



Hellmayr and Conover (Cat. Birds Amer., pt. 1, no. 1, 1942, pp. 

 375, 376) list the forms of Laterallus alhigularis as races of Laterallus 

 melanophaius (Vieillot), found from southeastern Colombia and 

 Venezuela to northern Argentina and Brazil. The two groups are 

 closely similar in color pattern, but in melanophaius the under tail 

 coverts are plain brown without markings, while in alhigularis this 

 area is barred heavily with black and white. An occasional alhigularis 

 has some brown markings in the area concerned, varying from a 

 faint cinnamon wash on the tips of a few feathers to a light suffusion 

 of cinnamon brown, that however does not obscure the pattern of 

 barring. This is found in only about 20% of the series of more than 



