BIRDS OF ARGENTINA, PARAGUAY, URUGUAY, AND CHILE 319 



Uruguay, February 7 and 8, belonged to the present species, but no 

 specimens were collected for identification. 



It is probable that there are two forms of subcristata in the range 

 as outlined in the opening paragraph above. The single specimen 

 secured from west of Puerto Pinasco and a few others seen from the 

 Chaco are paler below than birds from the Province of Buenos 

 Aires. Birds that in bright coloration resemble those of the south 

 were also secured at lias Palmas and Resist encia. It is possible that 

 the pale birds represent a resident form of the Chaco and that the 

 brighter ones are winter migrants from the south. 



>S. munda is so similar to &. KuhcHstata that it would appear that 

 the two should stand as subspecies of one form. However, west of 

 Puerto Pinasco, Paraguay, on the ranch known as Kilometer 80, I 

 found suhc7istafa and muiula ranging in the same forests without 

 evidence of intergradation, so that they must be considered specifi- 

 cally distinct. As S. inornata was taken there also, three distinct 

 species of Serpophaga were found at this point. 



Serpophaga suhcHstata is one of the familiar species of the for- 

 ested regions and brushy areas in the Chaco, that on the pampas 

 inhabits groves about the estancias, and in the more arid south is 

 found in heavy stands of Baccharis and Salix along the larger 

 streams. Though undoubtedly a flycatcher, it is so sprightly and 

 vivacious in its movements that in life it gives little suggestion of 

 its tyrannine affinities. In fact, as the birds flit and hop about 

 among the twigs, often calling or singing excitedly, they bear a 

 striking resemblance to warblers. During winter they Avere found 

 constantly with little bands of other little birds that ranged the 

 forests and came around without fear to inspect me, often hopping 

 out almost within reach. Both sexes sang frequently, a fact that I 

 established by collecting specimens, but the notes of males were 

 louder than those of the opposite sex. The entire song may be repre 

 sented as chois chois chee chee chee chee-ee-ee-ee^ a few twittering 

 notes followed by a hard trill, of which the first part was frequently 

 omitted. 



The first young bird seen, a male not quite grown, was taken De- 

 cember 29, near Victorica, Pampa. Other juvenile birds were re- 

 corded at San Vicente, Urugua3% January 31, and Rio Negro, Uru- 

 guay, February 14, In juvenal plumage subcristata is washed with 

 brown above, especially on the upper tail coverts, and has the wing 

 bars light-pinkish cinnamon instead of whitish. Beneath the birds 

 are whitish, and the black and white markings found in adults in 

 the crown are lacking. An adult female shot at Rio Negro, Uruguay, 

 Februar}^ 19, is in fall molt. 



The bill and tarsus in this species are black. 



