Sub-fam. 9. _Plectropterinae._–_Aex sponsa_,[118] the Summer Duck of North America and Cuba, accidental in Jamaica and the Bermudas, has the upper parts mainly glossy green, with purple cheeks, black neck-patches, and white stripes on the face and neck; the breast is chestnut with white spots, the throat and belly are white, the wing-coverts partly blue, the flanks brown, black, and white; the bill is black, white, yellow, purplish, and scarlet; the feet are yellow. It has a long occipital crest. The female is grey-brown with metallic gloss, a white throat and eye-space, plumbeous and black bill, and brownish feet. This inland species feeds on insects, seeds, leaves, and acorns, and lays buff eggs in holes in trees. _Aex galericulata_, the Mandarin Duck of East Asia, is somewhat similar, but has a neck-ruff of narrow chestnut feathers streaked with whitish, a chestnut and black "fan" formed by the decurved innermost secondary, a copper, purple, and green crest, and a red-brown bill. The female is brown, grey, and white. _Nettopus pulchellus_, of Australia, New Guinea, and the Moluccas, has the upper parts and neck-collar dark green, the head browner, the remiges and rectrices black with a white wing-bar, the cheeks and lower parts white, the sides marked with {134}green crescentic bands, and the bill and feet black. _N. coromandelianus_, extending from the Indian Region to Celebes, has a white neck, a brown band across the breast, and the flanks freckled with grey; _N. albipennis_, of East Australia, is similar but larger; _N. auritus_, of West and South Africa with Madagascar, has a sea-green patch on each side of the occiput, the lower part of the neck and the flanks being rufous. The females are much duller. These Pigmy Geese frequent small lakes and dive admirably; the note is a cackle; the nest, placed in holes in trees or ruins, if not among grass, contains from six to twelve white eggs. _Pteronetta hartlaubi_, of West Africa, is chestnut with black head and blue wing-coverts in both sexes. _Rhodonessa caryophyllacea_, of India and Burma, is rich brown dotted with whitish, the head and nape being pink, the speculum salmon-coloured, the bill reddish-white, the feet blackish. It lays round white eggs.