4 14 Mr. N. A. Vigors on the Natwal Affinities 



greater extent in the type of the Struthionidce, where one of the 

 front toes is also deficient. This character, which indicates the 

 habit of running, brings the Charadriada in a natural arrange- 

 ment into close contact with the Struthionida. So that we may 

 at once decide that the passage from the Gallinaceous to the 

 Wading order takes place at that point where the two extreme 

 subdivisions of the latter are united, as we shall shortly observe, 

 by the genera CEdicnemus of Cuvier and Psophia of Linnaeus. 

 The genus Otis, Linn, seems to be the group among the Rasores 

 that immediately meets them. 



The two conterminous orders, Grallatores and Natalores, form- 

 ing, when united, a division of the entire class, which may be 

 entitled Aquatic Birds, it may readily be concluded that they 

 approach each other by such gradations as render it no easy 

 task to fix the exact limits of each. This is so much the case, 

 that the most obvious characters of each order are in many in- 

 stances transferred to groups of the other. Thus we find the 

 webbed feet of the l^atatores among birds which do not swim, as, 

 for instance, the Recurvirostra, Linn., and Pha:nicopteriis, Linn. 

 On the other hand, we have groups which do swim, such as the 

 genera Rallus, Linn., Gallinula, Briss., and Ilcematopus, Linn., 

 and which yet possess the divided toes of the Grallatores. Again, 

 we may observe other Swimming Birds, such as the lobated Fti- 

 lica, Linn., and Phalaropus, Briss., the feet of which may be said 

 to be neither webbed nor divided, but to partake of each charac- 

 ter. Various modes of classing these birds have consequently 

 been adopted by systematic writers. Linnaeus has placed the 

 before-mentioned genera P/mnicopferus and Recurvirostra among 

 his Anseres, or our Nata tores. But the character of their webbed 

 feet is neutralized by the extreme length and forward position of 

 their legs, which totally prevent their swimming : and these lat- 

 ter characters, together with the nakedness of their thighs and 

 their habits of life, decidedly place them among the Grallatores. 



To 



