BLACK-BILLED TREE DUCK 171 



it is uttered not only during flight, but also at times when the birds are on the water 

 (L. C. Sanford in litt.). 



Food. The most noteworthy characteristic of the feeding habits of these birds, 

 and one that has been remarked again and again, is their practice of alighting in the 

 tops of royal palms and devouring the fruit. They are very fond also of the so-called 

 "guinea-corn" when it is in milk (Gosse, 1847; Gundlach, 1875). They are essen- 

 tially vegetarian in their diet and eat grass, seeds, berries, small fruits and on oc- 

 casion tadpoles. They were noted as being very particular to dip under water and 

 pound up any hard object, before eating it (English, 1916). 



Courtship and Nesting. The nesting season of the Black-billed Tree Duck ex- 

 tends from June to October in Cuba (Gundlach, 1875) though it must occasionally 

 nest earlier, for March (1864), speaking of Jamaica, states that young birds were for 

 sale in the markets as early as May. On Watling's Island, Worthington (Todd and 

 Worthington, 1911) found a deserted nest on February 20. All the Tree Ducks are 

 late nesters, and, being largely tropical species, their reproductive period is much 

 more extended than that of more northern ducks. Dr. Sanford's guide on Andros 

 Isle told him that he had found them with young in every month of the year. 



The courtship of this species has never been described, and I am unable to offer 

 anything beyond the general notes of Heinroth (1918) that all Tree Ducks indulge 

 in a peculiar lifting of the wings, which, possibly, may have some connection with 

 the exposure of the ornamental flank-feathers. 



Specific information as to the nesting localities is very sparse, many collectors 

 having relied chiefly on the stories of the natives. Gundlach (1875) was told that 

 they nested occasionally in tall palms, but according to his own observations the 

 nest is made of twigs and leaves, spread over parasitic plants, or formed on horizon- 

 tal branches, especially when overgrown with Tillandsia versiculata. A more recent 

 naturalist (English, 1916) found nests on Grand Cayman mostly of grass, without 

 down-lining, well hidden in dry places among bushes, while Worthington (Todd and 

 Worthington, 1911) found one on Watling's Island built between the roots of an up- 

 turned tree in the middle of a swamp. The eggs are from ten to twelve or sometimes 

 fourteen in number (March, 1864; Gundlach, 1875), milky white in color and meas- 

 uring about 55 by 40 mm. (Gundlach, 1875). The only observations as to the incu- 

 bation period were made by Mr. F. E. Blaauw on a pair of pinioned birds in his 

 aviary. They laid five eggs and hatched them in thirty days (Blaauw, 1912). 



Status. When Mr. Outram Bangs was collecting in Jamaica in 1907 an old negro 

 hunter told him that when the mongoose was first introduced into that island the 

 Tree Ducks were nesting on the ground, even in the open fields, and he used to see 



