328 Mr. H. Seebohm on the Genus Himantopus. 



writers who place such an extravagant value on structural 

 characters. In my opinion H. andiniis is a model represen- 

 tative of a Semi-stilt. It has the black mantle and wings of 

 the Stilts^ whilst its strain of Avocet blood crops up in the 

 less important characters of its recurved bill, webbed feet, 

 and hind toe. H. pectoralis, on the other hand, is an ex- 

 cellent Semi-avocet, its white mantle and the white on its 

 wings proclaiming it an Avocet, whilst its straight bill and 

 the absence of a hind toe show its relationship to the 

 Stilts. 



The third step in the argument is the apportioning of the 

 four groups to the four routes. The case is a very simple 

 one. The Semi-stilt and the Semi-avocet are, by the terms 

 of the hypothesis, the representatives of the two Pacific- 

 coast emigrations ; and as the Semi-stilt inhabits Peru, and 

 the Semi-avocet Australia, there can be no dispute that the 

 Semi-stilts emigrated along the American shores of the 

 Pacific, and the Semi-avocets along the Asiatic shores of 

 that ocean. The shores of the Pacific are so much more 

 mountainous than those of the Atlantic, that the ice of the 

 Glacial periods must have extended much further south on 

 the former than it did on the shore of the Atlantic, a cir- 

 cumstance which may account for the fact that the Semi- 

 stilt and the Semi-avocet both crossed the line and settled 

 in the cooler parts of the southern hemisphere. The Avocets 

 consequently represent the Old-World pair, the true Avocets 

 migrating along the Atlantic coast. The Stilts being the 

 New-World couple, we must apportion the Atlantic coast of 

 America to the true Stilts. 



Their further migrations must be considered when their 

 mutual relationships have been discussed. The first group 

 contains three species, which may be regarded as true 

 Avocets. 



HiMANTOPUS AVOCETTA. 



Avocetta avocetta, Briss. Orn. vi. p. 538 (1760). 

 Recurvirostra avocetta, Linn. Syst. Nat. i. p. 256 (1766) ; 

 et auctorum plurimorum. 



