THE CLASSIFICATION OF BIRDS 45 



maxillo-palatines not coalesced with each other ; ambiens muscle 

 present. 



GALLIFORMES. ^Egithomorphas with schizognathous palate, 

 holorhinal nasals, and an ambiens muscle. 



CUCULIFORMES. 



The Cuculidce, the Musophagidce, and the Upupidce agree to- 

 gether in certain characters in which they differ from the other 

 quineubital birds with normal plantars. They are the only birds 

 amongst the ^Egithomorphao which are desmognathous. They 

 further differ from the Passeriformes in having the spinal feather- 

 tract forked on the upper back ; from the Turniciformes in having 

 holorhinal nasals; and from the Galliformes in being hatched 

 blind, naked, and helpless. 



21. UPUP^. 22. CUCULI. 



The Musophagidce agree with the Upupidce in having the oil- 

 gland tufted. The Musophagidce further differ from the Cuculidce, 

 as well as from the Upupidce, in having the spinal feather-tract 

 interrupted at the base of the neck, but not divided on the back 

 by bare spaces. The Cuculidce have a vomer, which is not found 

 in the Upupidce or the Musophagidce. The Cuculidce and Muso- 

 phagidce possess the ambiens muscle, which is not found in the 

 Upupidce. They also agree in having more or less zygodactyle 

 feet, which is not the case with the Upupidce. Both carotids are 

 also present, whilst the Upupidce only possess the left one. There 

 will probably be little difference of opinion that the Cuculidce and 

 the Musophagidce may reasonably be associated together as Cuculi, 

 leaving the Upupidce to form the Upupce. 



The Cuculidce are distributed over the temperate and tropical 

 parts of both hemispheres ; the Upupidce are not found in the 

 New World ; whilst the Musophagidce are confined to Africa. 



into a saddle, which may contain (It) a central bare space as in Corvus, &c., or (c) 

 may be solid as in Passer, &c. 



None of these variations have been found amongst the Pelargomorphfc ; but 

 in the JEgithomorphas they occur in various groups outside the Passeriformes, 

 such as Turnices, Crypturi, and many of the Galli. 



Of the Coraciomorphze the Alcedinidce, the Todidce, the Momotidce, the Coliidce, 

 the Troyonidce, and all the families of the Scansores have the spinal feather-tract 

 well denned on the neck and not forked on the upper back. 



