of the Family of Anatidce. 1 5 



substantially correct, and, that a genus, so interpreted, is a 

 definite group *. 



The most superficial observer, on looking to the family 

 of the 



ANATID^E, or Ducks, 



under which he will include the geese and swans, must be 

 struck by the remarkable shape and structure of the bill, to- 

 tally different from that of all other birds. This, in fact, is 

 the only group in the aquatic order wherein the bill is very 

 considerably dilated in its breadth, and of a texture unusually 

 soft. In addition to these, a third, and a very important cha- 

 racter is discerned : the cutting margins of the bill are provided 

 with numerous transverse lamellar plaits, so much developed in 

 some species, as to project beyond the bill ; thus assuming an 

 analogy to the teeth of quadrupeds. This analogy, however, 

 is more imaginary than real, since these appendages are des- 

 tined for a very different purpose. The feet, although in 

 general short, are adapted to more than one purpose, since 

 they are not only used for swimming and diving, but for 

 walking. The adoption of this structure is in admirable unison 

 with their natural habits, and with the station that ALMIGHTY 

 WISDOM has ordained them to fill in the great empire of 

 Nature. The Gulls feed indiscriminately upon marine ani- 

 mals, whether living or dead : they are the purifiers of the 

 waters, as the Vultures are of the land. The Pelicans and the 

 Penguins derive their support from those large fish which the 

 more feeble Gulls can neither capture nor swallow, while the 

 Terns skim the ocean in search of small fish which rise to 

 the surface. But the inconceivable multitudes of minute 

 animals which swarm, as voyagers assert, in the northern seas, 

 and the equally numerous profusion inhabiting the sides of 

 rivers and fresh waters, would be without any effectual check 

 upon their increase, but for a family of birds destined more 

 particularly for that purpose. In the structure, accordingly, 



* Strange as it may appear, not one of Mr. Macleay's disciples have adopted 

 the views of their master on this highly important question. The definition of a 

 genus, given in the Zoological Journal, vol. iii. p. 97, &c., is diametrically opposed 

 to that of the Hor* Entomologies. The one is founded upon abstract reasoning, 

 the other upon demonstration. 



