420 



Natatokes.- 



-BIRDS- 



-Anatid.e. 



THE HOKNED SCREAMER {Palamedea corniita) — 

 Plate 28, fig. 105— is nearly allied to the Jacanas. Its 

 head is decorated with a singular long and slender 

 horn, and its wings are armed each with two spurs. 

 The toes, and especially the claws, are comparatively 

 shorter than in the true Jacanas. This hird is ahout 

 the size of a goose, and of a hlackish colour, with a 

 large red spot on each shoidder. It dwells in the 

 marshes of South America, living in pairs, and utters 

 loud cries which may be heard at a great distance. 

 It is said to live chietly upon leaves and seeds. 



THE CHAJA {Chauna chavaria), instead of the curi- 

 ous horn of the Screamer, has on the back of the head 

 a circle of feathers, which are capable of being raised 

 or depressed at the pleasure of the bird. The Chaja 

 is an inhabitant of Brazil and Paraguay; it feeds chiefly 

 on vegetable matters, and is frequently kept with the 

 domestic poultry, as it is said to drive away birds of 

 prey. This bird is remarkable for the looseness of its 

 skin, which appears to be separated from the subjacent 

 muscles by a stratum of air-cells, and tlie skin oackles 

 when the finger is pressed upon it. 



Order VIII.— XATATORES. 



In the Natatorial or Swimming Birds we find in its 

 higliest state of development a character which, as 

 already stated, occurs more or less amongst the mem- 

 bers of the precedhng order, namely, the union of the 

 anterior toes by a web or membrane. In fact, in most 

 of'iijiese birds the feet are completely palmated, the 

 ni'jmbranes extending quite down to the extremities of 

 the toes; but this is not universally the case, for in 

 some forms the toes are merely bordered with a wide 

 membrane. The posterior toe is almost always small, 

 more or less elevated on the back of the tarsus, and 

 directed a little inwards; in a few species it attains 

 a greater degree of development, and is then united by 

 a membrane to the inner anterior toe. By the agency 

 of these webbed feet the birds of this order are enabled 

 to swim with great ease and rapidity, and most of them 

 pass the greater portion of their existence upon the 

 tiirface of the water, not a few also being able to dive 

 and progress beneath the surface with astonishing faci- 

 lity. The legs are usually rather short, and placed very 

 far back towards the tail, a position which, coupled 

 with the boat-like form of the body, greatly increases 

 the natatorial power, but renders the gait of these 

 birds upon dry land awkward and waddling in the 

 extreme. In some forms, such as the Penguins and 

 skeleton, the legs are so placed that the bird is com- 

 pelled to hold itself quite upright when out of the 

 ■water. 



The body, as already indicated, is of an elongated, 

 boat-like form, admirably adapted for speedy motion 

 through the water ; it is generally stout and bulky, 

 and most frequently terminates in front in a rather 

 elongated and very flexible neck. The plumage is 

 dense, and exhibits a very thick under-coat of down ; 

 the outer surface is kept constantly greased by the 

 birds, so tliat the water runs off it with great readi- 

 ness. In other respects these birds exhibit many 

 and important diflerences amongst themselves. In the 

 development of the wings we find a far greater varia- 

 tion than in any other order of birds, some species 

 being endowed with enormous organs of flight, which 

 suffice to support them in the air for the whole day 

 without apparent fatigue ; whilst others have mere 

 rudimentary pinions, quite unfitted for flight. The 

 latter are the most thoroughly aquatic in their habits 



of the members of the order ; and between these two 

 extremes we find every intermediate grade. The bill 

 is also subject to great variations in size, form, and 

 texture. 



As might be expected from the preceding state- 

 ments, the habits of these birds vary greatly, and they 

 form six well-defined families, presenting important 

 difi'erences both in structure and mode of life. 



Fa.mily I. — ANATID^E. 



The birds forming this family, of which our common 

 Geese and Ducks are characteristic examples, arc 

 easily distinguished from all the rest of their order by 

 the peculiar characters presented by the bill. This 

 organ is generally of a rather broad and flattened 

 form, and furnished with a soft covering ; and the 

 edges of both mandibles exhibit a series of fine, tooth- 

 like lamellae or plates. The office of these, which 

 interlock when the mandibles are nearly closed, is to 

 form a sort of strainer, by means of which the birds 

 are enabled to separate small particles of food from the 

 water and mud in which they commonly seek their 

 nourishment. The feet are well developed, and the 

 anterior toes are united by ample membranes ; the 

 hinder toe is small, free, and raised more or less on 

 the back of the tarsus. The wings are also tolerably 

 large and powerful, enabling the birds, notwithstand- 

 ing their bulky and rather heavy bodies, to fly with 

 considerable ease and rapidity ; many of them are 

 migratory in their habits, and perform long journeys 

 to and from their breeding places. They are generally 

 gregarious, and most of them frequent fresh waters, 

 although they are often seen on the sea-shore in the 

 winter season. Their food consists chiefly of worms, 

 aquatic insects, and moUusca, which tlie}' obtain as 

 above described by straining the mud and water 

 through the tine lamellse of their bills. The species 

 of this family are very numerous, and we can only 

 refer to a few of the most interesting forms. 



THE FLAMINGO [Phanicopterus n(/-<)-)— Plate 29, 

 fig. 109. — This singular bird undoubtedly presents the 

 nearest approach in many respects to the preceding 

 order, although its characters distinctly show that it 

 belongs to the present family. It is supported upon 



