A NA TID^E — C YGNINJE : S WA NS. 



893 



feet), etc. This is the member of the Anatidce to which the Horned Screamer {Anhima cor- 



nuta) makes its oearest approach, aud indeed their resemblance iu several respects is evident; 



it is a large black and white bird, with the strut of a Crane rather than the waddle of a Goose. 



4. The Spur-vviuged Geese of the African genus Plectropterus, with certain of their allies, may 



form another subfamily Plectropterince. There are several species or subspecies of the genus, 



all having the wings spurred, the lores naked, and a curious fleshy knob on the forehead, best 



marked in P. riieppelli of Abyssinia. The limits of this subfamily are wholly iu question ; 



some writers consider that tlie Egyptian Goose, Chenalopex ccgyptiaca, and the similar South 



American C.jubatiis belong to it, while others refer Chenalopex to ordinary Anatince, aud bring 



under Plectropterince a number of other genera, among them Sarcidiomis, the ^ of which has 



a large fleshy comb at the base of the upper mandible. But in any event, in considering these 



birds we are already come upon quite ordinary forms of Anatidce, further remarks concerning 



which will be found under heads of the five subfamilies to be formally presented in the present 



work. 



Analysis of North American Subjamilies. 



Cygnin*:. Swans. Lores partly naked. Neck very long. Tarsi reticulate. Hallux simple. Sexes alike. 

 Anserine. Geese. Lores feathered. Neck moderate. Tarsi reticulate. Hallux simple. Bill high at base. Sexes 



alike. 

 ANATiNiE. JRiver Ducks. Lores feathered. Tarsi scutellate in front. Hallux simple. Bill flattened. Sexes unlike. 

 FuLiGULiN^. Sea Ducks. Lores feathered. Tarsi scutellate in front. Hallux lobate. Bill flattened. Sexes unlike. 

 Merging. Mergansers. Lores feathered. Tarsi scutellate in front. Hallux lobate. Bill cylindric. Sexes unlike. 



Subfamily CYCNIN/E: Swans. 



A strip of bare skin between, eye and hill ; tarsi reticulate, shorter than middle toe and 

 claw ; hind toe simple, or with very slight lobe. Neck of extreme length and flexibility, ex- 

 ceeding the trunk, with 22-24 vertebrae ; the movements and attitudes of Swans on the water 

 are elegant and graceful, especially in those species 

 which bend the neck in a regular sigmoid curve. 

 The bill equals or exceeds head in length ; it is high 

 and compressed at base (where sometimes tubcrcu- 

 late), flatter and widened at end, on the whole more 

 duck-like than goose-like ; the nostrils are median. 

 Lores naked in adults, feathered in young. Some 

 of the inner remiges are usually enlarged, and when 

 elevated in a peculiar jxisitiim of the wing act as 

 sails to help the course of the bird over the water. 

 Tlie legs are placed rather far back, so that the gait 

 is awkward and constrained on land, in striking con- 

 trast with tlie stately grace with which these birds 

 swim ; they waddle worse than Geese, quite as badly 

 as any Ducks, and " a Swan on a turnpike " is pro- 

 verbially ill at ease. Tail sliort, of 20 to 24 feath- 

 ers. The sexes are alike throughout the group. Although the voice of most species is sono- 

 rous at times, an habitual reticence of Swans, especially of the mute Swan, contrasts strongly 

 with the noisy gabbling of Geese and Ducks ; it is hardly necessary to add, tliat their fancied 

 musical ability, either in health or at the approach of death, is feigned by poets but not con- 

 firmed by examination of their vocal apparatus. The trachea is in several species convoluted 

 as already <lescribed, but there are no syringeal muscles nor other ajiparatiis for modulating the 

 voice musically. There are 8 or 10 species, of various countries, among them the celebrated 

 Black Swan of Australia, Chennpsis atrata. with peculiarly crisp, curly, inner wing-featliers, 

 and tlie Black-necked Sw.iii of South America, Sthr)i,II,l,s mrhinanniijiha (Ciioini" niaricoUis 



Fig. C'24. 

 Dixon.) 



■Mute Swan, t'l/t/ii'is 



