THE CLASSIFICATION OF BIKDS 25 



RALLIFOIIMES. Pelargomorphas with schizognathous palate, 

 holorhinal nasals, more or less vestigial hallux, and bill unfur- 

 nished with a cere. 



FALCONIFORMES. Pelargomorphae with holorhinal nasals ; bill 

 furnished with a cere ; hallux well developed and situated on the 

 same plane as the other digits ; spinal feather-tract well defined 

 on the neck ; and young hatched in a helpless condition. 



CICONIIFORMES. Pelargomorphse with desmognathous palate, 

 and with spinal feather-tract not defined on the neck. 



The Pelargomorphae appear to have been very successful in 

 the struggle for existence. The Columbas, the Psittaci, the 

 Accipitres, and the Striges still perch in trees ; whilst most of 

 the Gavias, the Pygopodes, the Steganopodes, the Anseres, and 

 the Tubinares are swimmers or divSrs. The Limicola3, the Grues, 

 and the Herodiones are many of them waders, and are half land 

 and half water birds. 



CICONIIFORMES. 



Probably few persons will object to the association of the 

 Steganopodes with the Herodiones and the Anseres. They are 

 all desmognathous, and in none of them is the spinal feather- 



we may suppose that free maxillo-palatines are a primitive character; but 

 desmognathous palates are found in all the Ciconiiformes, in the Psittaci, and 

 Accipitres amongst the Falconiformes, in more than half the families of the 

 Coraciomorphas, and in all the Cuculiformes. Further evidence that free 

 maxillo-palatines are a primitive character is to be found in the fact that in 

 newly-hatched examples of many desmognathous birds the maxillo-palatines 

 have not yet coalesced. 



t Garrod and Forbes attached great importance to the bifurcation of the 

 nasal bone, of which they recognised two modifications : 



Holorhinal. Angle of bifurcation rounded off and placed forwards, so that a 

 line drawn across the skull at a tangent to the two curves falls in front of the 

 lachrymals and the termination of the nasal processes of the premaxillary. 



Schizorhinal. Angle of bifurcation in most cases very acute, but occasionally 

 rounded; always placed backwards so that the apex extends as far back as the 

 posterior terminations of the nasal processes of the premaxillary between the 

 centres of the lachrymals. 



Schizorhinal birds occur both in the Pelargomorphae and in the JEgitho- 

 morphaj. In the former subclass the Charadriiformes are all Schizorhinal, and 

 amongst the Ciconiiformes the Ibididcc, a small family of Herodiones, appear to 

 have independently acquired the same peculiarity. In the latter subclass the 

 Turniciformes are all schizorhinal, and amongst the Passeriformes it appears 

 that there are half-a-dozen small genera of mesomyodian Passeres which have 

 also independently become schizorhinal (Garrod, "Proceedings of the Zoological 

 Society," 1877, p. 449). All other birds are supposed to be holorhinal. 



