368 ANAS QUERQUEDULA 
pared by Rogeron (1903) to the sound produced by passing a wooden ruler over the 
teeth of a coarse comb. It is constantly uttered during courtship. At least two such 
reliable observers as Naumann (1896-1905) and Baker (1908) have distinctly said 
that in autumn and winter the male utters a note which is the same as the knak of 
the female; but I cannot reconcile myself to the belief that any of the northern 
surface-feeding ducks have a note common to both sexes, excepting in the first 
months of life. Possibly the young male does not get his fully developed voice until 
late in the first winter. 
The note of the female, as already stated, is a quack, less loud, but in a higher key 
than that of the Mallard, and this note has given it the German name “Knakente.” 
Little chattering notes, which are not call-notes, are common to both sexes, as in 
other ducks. 
The trachea of the male is about 180 mm. long and is very distinctive, quite unlike 
that of any related species. The diameter of the tube increases in size toward its 
lower end and merges into a large oval tracheal pouch which faces forward and is 
not left-sided or transverse like the bulla ossea of most ducks. The tracheal tubes 
spring from the inner flattened surface of this pouch, and not from below it, as in 
many species. 
Food. It is difficult from the scattered observations to make any fair comparison 
between the diet of Garganeys and that of other Teal. They are chiefly vegetable 
feeders, but at the same time a great deal of animal food is taken, particularly on the 
breeding grounds in northern Europe. Millais’ (1902) statement that they feed 
largely on small fish and aquatic insects must be based on observations made under 
exceptional conditions. Nevertheless so many writers have spoken of their rather 
inferior flesh, that the conclusion is almost forced upon one that the species is less 
of a vegetarian than the Common Teal, and perhaps even more of an animal feeder 
than our own Blue-wing {Anas diseors). Naumann (1896-1905) included among the 
food, insects, insect larvae and all kinds of small worms, tender roots, sprouts and 
leaves, seeds of all kinds of water-plants, earthworms, snails, very small frogs and 
frog spawn, and occasionally very small fish and fish-spawn. Stomachs examined 
by Jackel contained snails {Planorbis hispidus), leeches {Haemopis vorax), water- 
bugs {Naucoris cimicaides) , caddis-fly larvae and their cases, and various water- 
beetles {Parnus, Hydrobius, Cyclonotum), in addition to seeds of pond-weeds, rushes, 
sedges, manna-grass, pond-lilies, smart-weeds, dock and water crowfoot {fide Nau- 
mann, 1896-1905). 
In India, according to Hume and Marshall (1879) they also feed on wild and culti- 
vated rice, and those on the seacoast consume shrimps, delicate shells and other 
animal substances. Stomachs of two birds shot in India in April contained small 
shells {Planorbis) and bulbous water-weed roots, besides other snail shells, bivalves 
