BIRDS OF ARGENTINA, PARAGUAY, URUGUAY, AND CHILE 251 



female, July 26) ; Riacho Pilaga, Formosa, August 11 and 18 (two 

 males, taken on the latter date) ; and Tapia, Tucuman, April 7 to 

 13 (an immature female, shot April 7). There is no appreciable 

 difference in appearance in specimens from the three localities rep- 

 resented by the five birds preserved as skins. The association of this 

 and allied straight-billed forms in the genus Ufucerthia with spe- 

 cies of the U. dumetaria type is questionable. 



These birds of wrenlike appearance and action inhabited heavy 

 brush where they worked about on or near the ground, in such dense 

 cover that it was difficult to observe them. At any alarm they gave 

 vent to loud whistled calls, suggestive of those of a canyon wren, 

 and at times were called out by squeaking noises. Their notes are 

 loud and might easily be attributed to a bird of greater bulk. 



In an immature male the maxilla and tip of the mandible were 

 dull black; base of mandible pallid brownish drab; tarsus and toes 

 fuscous. 



UPUCERTHIA LUSCINIA (Barmeister) 



Ochetorhynchus Luscinia Burmeister, Journ. fiir Ornith., 1860, p. 249. 

 ( Mendoza. ) '* 



The present species was encountered only on a dry flat above the 

 city of Mendoza, Province of Mendoza, western Argentina, on March 

 13, 1921, when a female was taken. The few noted Avere found in 

 low brush along a dry wash. 



This bird has been treated as a geographic race of U. cei^thioideSy 

 a usage not borne out in my opinion by examination of specimens, 

 since luscima^ in addition to larger size, much more robust form, and 

 more grayish coloration, has a decidedly longer tail and broader rec- 

 trices. The difference between the two is so extensive that any in' 

 tergradation, indicating subspecific relationship, must be considered 

 extremely doubtful unless it may be definitely proved by specimens. 



CINCLODES FUSCUS FUSCUS (Vieillot) 



Anthu8 fuscus Vieillot, Nouv. Diet. Hist. Xat., vol. 26, 1818, p. 490. 

 (Montevideo and Buenos Aires.) 



At Berazategui, in the Province of Buenos Aires, several were 

 seen and a male was taken on June 29, 1920, on low ground near the 

 Rio de la Plata. An immature male Avas shot at El Salto, at an ele- 

 vation of 1,600 meters above Potrerillos, Mendoza, on March 19, 1921. 

 This second specimen has several white feathers in the crov.n, an 

 albinistic tendency. It is darker brown than the one shot near 

 Buenos Aires. 



These birds walk on the ground with constantly wagging tails, and 

 when flushed may fly, with a flash of the light band in the wings, to a 



** According to Ilartert (Nov. Zool.. vol. 16, December, 1909, p. 208). 



