160 DENDROCYGNA AUTUMNALIS 



Gait. They stand high on their long legs, holding the neck erect or curved slightly 

 backward (Rogeron, 1903), and frequent the land more than the water. They are 

 able to walk long distances, and in Costa Rica the semi-domesticated birds were 

 seen toddling along in lines (Carriker, 1910). Hubbard (1907) credits them with the 

 ability to run at a great rate. 



Swimming and Diving. Though the earlier writers (Lawrence, 1874; et at.) 

 remarked that these birds were seldom seen on deeper waters, they do at times learn 

 to dive when kept pinioned on enclosed ponds (Hubbard, 1907). 



Perching. The Black-bellied Tree Duck seems to perch less freely than some of 

 the other Tree Ducks. In the nesting season, however, it is frequently seen in trees, 

 and it often alights on corn-stalks. One gets the impression from observing pin- 

 ioned birds that they care nothing about perching, for they are usually seen standing 

 by the edge of the water. Rogeron's were almost never observed off the ground, 

 even though some enjoyed the use of their wings. Only once or twice did he find 

 them awkwardly perched on wire fencing. Nevertheless one keeper in a zoological 

 garden told me that his specimens perched rather frequently. 



Association with other Species. Nothing recorded. 



Voice. Both this species and the very closely related Dendrocygna discolor are 

 distinguished from other members of the genus by having similar and sharper, as 

 well as louder voices. There is in the male the same tracheal enlargement de- 

 scribed under Dendrocygna arcuata and other species, and this enlargement is 

 strengthened posteriorly by a strong bony bar, or keel. The windpipe of the female 

 is not modified posteriorly as in the case of the Dendrocygna arcuata for example 

 (Beddard, 1898). The note itself has been described as loud, shrill and discordant, 

 uttered chiefly when on the wing (Nutting, 1882). Grayson (Lawrence, 1874) has 

 likened it to a peculiar whistle sounding like the syllables pe-che-che-ne, which is 

 the name given the birds by the natives of Mexico. 



Food. Nothing appears to be known of the natural food of these birds, but sev- 

 eral observers have spoken of their fondness for Indian corn (maize) . When the corn 

 is nearly ripe they alight on the stalks, strip the husks from the ears, and pick the 

 grain off the cob (Sennett, 1879). They no doubt also graze after the manner of the 

 true geese, and other species of Tree Ducks. 



Courtship and Nesting. Although so little has been recorded as to the intimate 

 breeding habits of this species one must conclude that it is a tree-nester, perhaps 



