494 Mr. N. A. Vigors on the Natural Affinities 



latter character is still further developed in the ensuing genus 

 Porphyrio, Briss., where the base of the bill exhibits a considerable 

 degree of robustness ; and is also carried on to Fulica, which im- 

 mediately adjoins Porphyrio. The species that compose the true 

 Gallinula and Porphyria may be observed to possess a narrow 

 membrane on each side of the toes, which extends along their 

 whole length, straight and entire. We thus recognise the gra- 

 dual approximation of these genera to the lobated foot of Fulica 

 and Podoa, which unite the swimming Waders to the true web- 

 footed Nata tores. The dilatation of the upper mandible into'a flat 

 crown upon the forehead, which characterizes the latter groups 

 of this family, together with the same length of the toes, is found 

 to exist in some species of Parra ; and thus we are led back to 

 the groups from which we commenced our observations on the 

 family. 



We are introduced to the family of Charadriadce, or the three- 

 toed Waders, by means of HcBmatopus of Linnaeus, which indi- 

 cates its affinity to the lobated Fulica oi the last division by the 

 rudiments of the membrane that extends along the toe. This 

 character is sufficiently discernible in the species so frequent on 

 our coasts ; but it is so far conspicuous in an iiustralasian species 

 as almost to give its foot the appearance of being perfectly lo- 

 bated. This genus by its habits of swimming preserves an affinity 

 with the natatorial groups of the preceding family of Rallidce ; 

 and these again being connected with Phalaropus, which forms 

 an extreme genus of the Scolopacida, the whole of the Wading 

 Birds that possess the faculty of swimming are brought together 

 into one contiguous group. Besides Hamatopus, the present 

 family consists of A renaria, Briss., our common Sanderling ; to 

 which I feel inclined to add Strepsilas, 111., and Vanellus, Briss., 

 which have been separated from Tringa and generally assigned 

 a place near A renaria. It is true that both these genera possess 



a hind 



