150 BULLETIN 133^ UNITED STATES NATIONAL MUSEUM 



that might contain 100 individuals. On their wintering grounds 

 they were rather silent, but with the opening of northward migration 

 resumed their habit of uttering musical though noisy calls when 

 disturbed in any manner. On the pampas they congregated during 

 drier seasons about lagoons and flocks often sought refuge from the 

 violent winds that swept the open plains behind scant screens of 

 rushes. After any general rain these flocks dispersed to pools of 

 rain water in the pastures, where insect food was easily available. 

 The winter population was thus not stationary, but shifted con- 

 stantly with changes in the weather. By the first of March the 

 lesser yellowlegs had begun their northward movement and numbers 

 were found near Guamini, where they paused to rest after a north- 

 ward flight from Patagonia. In their case, as in that of other 

 migrant species from North America, it was instructive to note that 

 the migration southward came in September and October when the 

 birds traveled southward with the unfolding of the southern spring 

 and that the return northward was initiated by the approach of 

 rigorous weather in faraway Patagonia. Migrant flocks, many of 

 whose members offered sad evidence of inhospitable treatment at the 

 hands of Argentine gunners in the shape of broken or missing legs, 

 were noted on the plains of Mendoza, near the base of the Andes, in 

 March. And during early April the migration became a veritable 

 rush so that on the night of April 5, at Tucuman, the air was filled 

 with the cries of these and other waders in steady flight northward 

 above the city. 



The lesser yellowlegs seems to undergo a complete winter molt 

 while in the south. Two females secured September 6 and 21 at 

 Kilometer 80, Puerto Pinasco, Paraguay, have both body and flight 

 feathers worn. A female from Lazcano, Uruguay, taken February 

 7, is renewing the two outermost primaries in either wing. The 

 other primaries, the secondaries, and the tertials, as well as the wing 

 coverts, are new feathers, and the body plumage is in process of 

 renewal. Another female killed at Guamini March 8 has the wing 

 feathers entirely replaced and new plumage appearing on the body. 



Like the greater yellowlegs, Totanus flavipes has been reported in 

 Argentina from May to August, but it must be assumed, on the basis 

 of crippled individuals. 



The generic relationships of this species have been discussed in the 

 account of its larger brother T. nielamoleucus. 



TOTANUS MELANOLEUCUS (Gmelin) 



Scolopax melanoleuca Gmelin, Syst. Nat., vol. 1, pt. 2, 1789, p. 659. (Cha- 

 teau Bay, Labrador.) 



The generic relationship of the two yellowlegs to one another and 

 to related shore birds has been subject to considerable difference of 



