Fam. I. PALAMEDEIDAE.–In this group the head is small and the neck long, while the ribs have no uncinate processes, an archaic feature only found elsewhere among Birds in _Archaeopteryx_. The {109}bill is short and Fowl-like, with a blunt decurved tip, a covering of soft skin, and more or less of a cere; the tibiae are partly naked, the entirely reticulated metatarsi moderately long and fairly stout; the toes are elongated and have strong claws, but only rudimentary anterior webs; the wings are ample and somewhat rounded, with eleven primaries and about sixteen large secondaries; the tail has fourteen broad feathers in _Palamedea_ and twelve in _Chauna_.[106] Very noticeable are the two sharp spurs on the carpal portion of each wing, of which the foremost is the biggest; while in the even distribution of the body-plumage this Family recalls the Ratitae and the Spheniscidae. The sexes are alike; the nestlings, where known, are clad in yellowish-brown and grey down, the wing-spurs being developed in the earliest stages. The following account of the habits of _Chauna cristata_,[107] the Chajá or Chaka, must stand for those of the Family, in default of further details concerning the more northern forms. This striking species is a common resident in the swamps and brackish lagoons of Argentina, where the islands of the intricate morasses often hold flocks of more than a hundred individuals, the separate pairs being said to mate for life. The flight is slow, with powerful strokes of the wing, the birds being greatly addicted to soaring in spiral circles until they are hardly visible, and at times floating lazily upon the breeze. They rise noisily from the ground with laboured action, and are occasionally seen to perch in trees; but they are by nature waders which swim with considerable facility, and, when they do so, their bodies shew well above the water, owing no doubt to the same pneumaticity which causes a crackling noise to be heard when the skin is compressed. The food consists of succulent water-plants, seeds, clover, and so forth. The loud cry, uttered with the head thrown back when the performer is on the ground, may be heard at a distance of two miles, the male giving vent to a "cha-ha" and the female replying with a "cha-ha-li." The regular period for reproduction is the southern spring–September and October–but it is a remarkable fact that breeding takes place also in autumn and even winter; the nest being a massive structure of reeds and rushes slightly hollowed above, and standing some two feet high with its foundations in water, or, {110}in exceptional cases, floating. This nest is placed in some narrow channel or near the side of a lagoon, and contains from four to six oval buffish-white eggs. The female rises silently when disturbed, nor do the parents usually attack an intruder; but wounded birds are dangerous to approach, and make good use of their sharp spurs. The