PHYLOGENETIC 53 



one of the Accipitres, and this on account of its rather close 

 resemblance to the long-legged " Secretary-bird " {Serpentarius). 

 There can be no doubt, however, as to its Gruine character, 

 and it would seem that it is to be regarded as a near ally of 

 the extinct giant Phororhaais, also of South America. 



The Bustards {Orialidce) are certainly aberrant and isolated 

 members of the Crane tribe, though by the older Ornithologists 

 they were regarded as giant Plovers. 



The true Cranes alone remain to be mentioned, and of them 

 but little need be said here. The earlier systematists associated 

 these stately birds with the Storks, a mistake which is commonly 

 made to-day by those who judge merely from superficial ap- 

 pearances. Even by external characters, however, they may 

 be distinguished, the Cranes having a relatively shorter, less 

 cone-shaped beak, which is deeply grooved on either side, and 

 has the nostrils placed nearer the middle than the base. Ana- 

 tomically the difference between Storks and Cranes is so 

 wide that there can be no question as to the distinctness of 

 the two types. 



The Charadriiformes, as has already been remarked, are 

 close allies both of the Crane tribe (Gruiformes) and Fowl 

 tribe (Galliformes), these three great groups being probably 

 descendants of a common stock : though Dr. Chalmers Mitchell 

 — the latest original contributor to this subject — prefers to 

 regard the Gruiformes as an offshoot from the Charadriiform 

 stem. But it must be stated, in justice to him, that this con- 

 clusion is based only on the evidence of the intestinal con- 

 volutions, and was never intended to be regarded as a definite 

 decision. No one, indeed, would be less likely to allow the 

 deductions from a single character to form the sole basis for 

 determining so difficult a problem. 



But be this as it may, this group appears to present two or 

 three more or less sharply defined grades of development, and 

 these again present within themselves many phases of specialisa- 

 tion. 



There seems to be but little doubt but that the Curlews, 

 Dunlins, Sandpipers, Avocets and Plovers, for example, must 

 be regarded as the final stages in the evolution of the typical 

 Plovers. More primitive are the Thick-knees or Stone-curlews 

 {(Edicnemidce), Pratincoles and Coursers {Glareolidm), Seed- 



