SYSTEMATICALLY ARRANGED BY DR. T. T. KAUP. 
They feed only on fish, and are most rapacious and voracious.* If 
we consider these characteristics, collected from the pelican and the 
Pisces , in order to assign to the other families or suborders their 
fixed station, we give to the Picidce ( Bucconince et Picince ), among 
the Zygodactyly the fourth rank, on account of their extreme rapa- 
ciousness and voracity, the great development of their tongue and its 
ligaments, their stiff and rigid wing and tail-feathers, and sharp and 
curved claws. 
We assign the fourth rank to the Dentirostres , because in the 
fourth family Laniidce , we find the longest crooked bill and the 
greatest rapacity. 
The Ardeidce show the widest jaw, great voracity, and rapa- 
ciousness, the longest toes, and the pectinated middle claw. This 
family assumes to itself, and all Cultrirostres , the fourth rank as 
suborder. 
In the Gallinae, the ravenous bird type is but faintly indicated 
in the form of the bill of the family Tetraonidce. Among the 
Accipitres we give the fourth rank to the Gypaetidce , because in this 
isolated form they clearly show the pelican type, by a straight bill, 
curved upon the tip, with a furrow on the side (a remainder of the 
compounded bill), by well developed ligaments of the tongue, and an 
extraordinary power for flying, and an almost incredible voracity. 
Among the Falconidce, Pandion assumes to itself and all Aqui- 
line, the fourth rank as a genus, by feeding only on fish. 
According to the analogies taken from the Felicanidce, Gypae- 
Ude, and Pandion, the genera of Falconidce arrange themselves as 
follows : — 
Among the Falconince the true falcons take the fourth rank, 
because they have the longest toes, and greatest voracity. Among 
the Milvine , Elanus takes the same rank on account of its wide 
jav, great voracity, and round claws like Pandion. 
Among the Accipitrince, the fourth rank is assumed by Astur, 
because it Las the longest toes, and the greatest rapaciousness and 
voracity. 
xlnd among the Buteonine the fourth rank is occupied by Rost- 
In all forms where the pectmated middle claw appears, the greatest voracity 
has been observed, and may be supposed, if the mode of life be yet unknown is 
■nthe Permoptmts pileatm fsubg. caprornis), stria,, rostrhamas, ard eidm qhreola 
Cttmrius, hmosa, melamtra, corpus frugtfegus, the Caprimulginte 3 
