86 
HISTORY OF THE PARROTS. 
it is also a native. The passage from the Ring-Par- 
rakeets to the smaller American species, appears to 
be effected through those species in which the two 
central tail feathers begin to lose the peculiar cha- 
racter of the typical form, and the culmen of the 
bill assumes the ridged or triangulate shape that pre- 
vails in that American group of which Psitt. cruen- 
tatus, Temm., may be taken as an example ; these 
are followed by the larger species, as Psitt. Carali- 
nensis and Patachonica, which lead to the Maccaws 
by such members as have the cheeks partly feathered. 
Following the naked cheeked maccaws, we would 
place the true Psittacara, in which the orbits and 
part of the face is also naked, and the bill large and 
powerful, such as Psitt. acuticaucla, nobilis, &c. 
The passage to the next subfamily, or Psitticina, 
seems to be through Psitt. macrorynchus ( Tany - 
gnathus macrorynchus , Wag.), and other species, in 
which the tail loses its elongate and graduated 
shape. 
