PALMIPEDES. 357 



ORDER VI. 



THE PALMIPEDES. 



The feet, endowed with an adaptation for swimming, that is to say, 

 situated posteriorly in relation to the body, sustained on a series of tarsi 

 which are short and compressed, and palmated between the toes — these 

 peculiarities characterize the order. With a plumage dense and glossy, 

 whilst it is ever moistened with an oily excretion, and furnished near the skin 

 with a thickly-set down, they are protected against the water, the element 

 on which they live. Further, they are the only birds in which the neck 

 exceeds — and in some cases this excess is considerable — the length of the 

 feet, because in swimming on the surface they have often to search deeply 

 beneath it. Their sternum is unusually long, and it affords an ample se- 

 curity to the greater portion of their viscera, as it has on either side 

 merely one emargination or oval foramen furnished with membranes. 

 Their gizzard is usually muscular, the caeca long, and the inferior larynx 

 simple ; in one family, however, the latter is so inflated as to form carti- 

 laginous capsules. 



This order admits of n tolerably precise division into four families, 

 and we commence with 



FAMILY I. 



THE PLONGEURS, OR BRACHYPTERES. 



The Divers, of which a portion bears some external resemblance with 

 those of the Gallinula : their legs being placed more posteriorly than they 

 are in all other birds renders their walking a painful process, and re- 

 quires of them, when on land, to stand in a vertical position. Besides, as 

 most of them are very indifferent flyers, and as several are unable to fly 

 at all, in consequence of the extreme shortness of their wings, we are 

 forced to regard them as almost exclusively attached to the surface of the 

 water : and hence is it that their plumage is so dense, and that it pre- 

 sents a surface very smooth and with a silvery polish. They swim be- 

 neath the waters, with the assistance of the wings, which serve as so 

 many fins. Their gizzard is muscular, and the caecum is moderate : they 

 have a distinct muscle on each side on the inferior larynx. Amongst these 

 birds the genus 



