206 ANAS SIBILATRIX 
in the company of this Pintail, though the Widgeon always stayed together even in 
such mixed flocks. 
Voice. According to Rogeron (1903) the note of the male is the same as that of 
Anas penelope, and Lane (1897) also speaks of it as a “ Wigeon-like whistle.” P. L. 
Sclater and Hudson (1889) describe it as three or four long clear whistling notes 
followed by another, and concluding with a kind of flourish, andde Beauquesne (1911) 
speaks of three notes of greater fullness and softness than those of the European 
Widgeon. A mated pair seen flying about in November uttered a high-pitched nasal 
quack and occasionally a grunt in the same tone. Mr. Peters, to whom I am in- 
debted for this note, thinks both sexes uttered this cry, but I must say that this 
seems to me unlikely. Heinroth (1911) says the note of attraction of the male, 
though very similar to that of Anas penelope, can nevertheless be distinguished from 
it and he notes that, in contrast to most other ducks, the female’s voice, which is a 
rather weak rattle, is much softer than that of the male. 
The trachea is about 155 mm. long and the tracheal bulb, which faces to the left 
and forward, is roughly spherical and very large. It is 25 to 28 mm. long and 20 to 
22 mm. broad. In other words this remarkable structure is about three times as 
large as that of the European Widgeon and perhaps five times the size of the 
American Widgeon’s. 
Food. Very little is known of the feeding habits of this species. Durnford (1878) 
saw the birds feeding on the extensive mussel-beds at the mouth of the Chubut, and 
A. H. Holland (1892) says they feed on high ground among dry thistles, or even in 
the open. No doubt they are to some extent upland feeders like their relatives, and 
it is doubtful whether they ever take much coarse animal food. Crawshay (1907) 
found grass in the stomach of a specimen shot in Tierra del Fuego and in captivity 
they graze like Anas penelope (Rogeron, 1903). 
Mr. Peters collected eight stomachs at Huanuluan, Rio Negro Province, between 
August 25 and November 12, 1920. These contained nothing but vegetable matter 
and gravel. The shoots of a rush (Juncus) were by far the most important food and 
were present in five stomachs in large amount. Water crowfoot (Batrachium) was 
well represented in three stomachs (96 to 100%); and there were a few seeds to as 
many as 150 seeds of water milfoil {Myriophyllum) in six stomachs; sedge {Scirpus 
americanus) was poorly represented in only two of them (examination by U.S. Bio- 
logical Survey). 
Courtship and Nesting. Like the other Widgeon this is a late nester, certainly 
much later than Anas spinicauda (Peters, MS.). The season varies of course with the 
locality. According to de Beauquesne (1911) Widgeon are paired by August or Sep- 
