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ANAS OXYPTERA 
more common in the south, especially about Lake Titicaca and in Arequipa (J. A. Allen, 1875; 
Taczanowski, 1886; Brewster-Sanford collection; Menegaux, 1909a; von Berlepsch and Stolzmann, 
1906). P. L. Sclater and Salvin (1869a) have also recorded it from Tungasuca and the vicinity of 
Tinta, and F. M. Chapman (1921) reports a specimen in the Occobamba Pass, not far from Cuzco. 
In western Bolivia the species has so far been found chiefly in the vicinity of Lake Poopo. hlcne- 
gaux (1909a) has recorded it from Tamarape, Sicasica and Pazna Bastide. 
In northern Chile, so far as I know, the species has been found only in the Provinces of Tacna and 
Tarapaca. The dividing line between Anas oxyptera and Anas flavirostris in this region is not yet 
clear. Taczanowski (1886) has recorded it from Tacna and the vicinity of Cuterv'o, and P. L. Sclater 
(1886) says it was taken by Berkeley James at Sitana, Huasco, Sacaya and Lalcalhuay in the Prov- 
ince of Tarapaca. It has also been taken at Calalaste, Tarapaca (Philippi, 1888) but Lane (1897) 
found it not common near Sacaya. 
From the Argentine the species has been recorded for the northernmost Provinces only, Jujuy and 
Salta (Bruch, 1904), but I strongly suspect that some of the records for Anas jlaviTostris from this 
region should be referred to this species. 
GENERAL HABITS 
This duck is very similar to the preceding species (Anasflavirostris) in appearance, 
although the difference in the downy young is very striking. This is a remarkable 
fact, if the distinction always holds as well as it does in the few specimens I have 
seen. 
The present species is confined to high Andean plateaus, reaching altitudes of at 
least 13,000 feet in Peru. Practically nothing has been recorded concerning its habits, 
breeding, voice, status, etc. Young have been obtained at Lake Titicaca in February 
(J. A. Allen, 1875). A large series taken by R. M. Beck at Lake Junin in March 
and April, 1913, and at Lake Titicaca in August (Brewster-Sanford collection) shows 
the following peculiarities: of eleven males from Lake Junin several had moulted the 
primaries; the sex organs of these males were either small or medium-sized, and none 
of them was in a breeding condition. One male taken at Lake Titicaca, August 18, 
was breeding. Of the seven female specimens, those taken in March had the sex 
organs either small or beginning to swell, while in one the ovaries were large. In a 
female specimen taken at Lake Titicaca on July 26, the sex organs were swelling. 
The breeding season therefore seems to be very irregular in that even climate. 
