MONOGRAPH OF THE FALCON1DJ3, 
subgenera ; among these are the following : — Erythropus = Tin- 
nunculus ; Hypotriorchis and Hierofalco = Falco; Strigiceps = 
Circus ; Gampsonyx = Elanus ; Lwmaetus and Spizastur = Spi- 
zaetus ; Micronisus and Atelier ax = Astur ; Morphnus, Thra- 
saetus = Asturina ; Herpetotheres, Gymnogenys , and Spilornis = 
Circaetus ; Ichthyaetus = Pandion ; //afo’as£wr==Haliaetus ; Ar- 
chibuteo = Buteo ; Baza and Cymindis — Pernis ; Daptrius and 
Milvago = Ibicter. 
As nominal subgenera, the following have resulted: — Pceci- 
lopteryx = Ictinia ; Hydroictinia = Milvus ; Craxirex = Astur ; 
Buteogallus — Rupornis ; Spizigeranus = Rupornis ; Brachyp- 
terus= Herpetotheres ; Avicida= Baza. 
Having indicated five fundamental types always recurring in 
the families of Aceipitres , as well as in the subfamilies and genera 
of Falconidce, I have shown how, by a misunderstanding of these, 
all ornithologists have been led to make use of them in the most 
diversified ways, in order to connect the genera and subgenera. 
Since they have not as yet been arranged under their true genera 
in any work on natural history, it may be conceived how Vigors 
and Swainson were not able to succeed in carrying through the 
quinary system ; not to mention that their arrangements were not 
founded on any consistent basis, since they had not comprehended 
the well-founded theory first proposed by Oken. 
By my investigation of the Falconidce , I think I shall also show 
on what weak foundations our present systematizing rests, and 
how the use of analogies, in order to connect families, subfamilies, 
genera, and subgenera, opens the way to arbitrary arrangement; 
and how, for instance, the existing Falconidce might be arranged 
in a thousand different ways without exhausting it. It is not, 
however, my intention to show here how the families, subfamilies, 
genera, and subgenera, may be connected according to erroneous 
analogies, since this has been more than sufficiently shown already, 
by ancient as w r ell as modern ornithologists. 
In a fit, as I think, of just chagrin, I gave a prescription (in the 
Isis, 1847, p. 47) how many hundreds of systems of the Falconidce 
may be contrived, which all might present some show of being 
founded on nature. However, I rather doubt whether this ironical 
treatment will save ornithology from new systems, in which all 
forms w ill be knit together, like a string, by wrongly used analogies, 
60-2 
