On the Affinities of the Falconidce. 319 



is quite correct ; and as the centre of which we may take the 

 most typical group of that family, viz, the Falcons properly 

 so called, and from them, on either side, we have a group of 

 genera arranged. As the type of the genus Falco, we take 

 the Falco communis, or Peregrin Falcon ; from it we are gra- 

 dually led on to the genus Hierofalco ; from it to Cerchnis ; 

 from this genus to Hierax ; from Hierax to Harpagus ; from 

 Harpagus to Astur ; from Astur to Accipiter ; from Acci- 

 piter to Morphnus ; from Morphnus to Pandion ; from Pan- 

 dion to Cymindis ; from Cymindis to Haliaetus ; from Haliae- 

 tus to Aquila ; from Aquila to Circaetus ; from Circaetus to 

 Harpyia ; from Harpyia to Torathropius ; from Torathropius 

 to Ibycter ; and from Ibycter to Daptrius. 



Again, when we proceed on the other side from the genus 

 Falco properly so called, we have first the long winged typi- 

 cal Falcons ; as a type we may take the Falco vespertinus of 

 Europe, adopting the generic name Erythropus of Boie, and 

 from it we are led into the genus Elanus ; from Elanus to 

 Nauclerus ; from Nauclerus to Milvus ; from Milvus to Gy- 

 paetos ; from Gypaetos to Brevitarsus ; from Brevitarsus to 

 Pernis ; from Pernis to Buteopernis ; from Buteopernis to 

 Ictinia ; from Ictinia to Buteo ; from Buteo to Circus ; from 

 Circus to Serpentarius ; from Serpentarius to Bacha ; from 

 Bacha to Polyborus, which is connected again with the last 

 genus in the upper series, and both of the terminations of 

 the circle are connected to the Vultures through the genus 

 Neophron. This arrangement may be represented in the 

 following table : — 



"Daptrius, 

 Ibycter, 

 Torathropius, 

 Harpyia, 

 Aquilidse. < Circaetus, 

 Aquila, 

 Haliaetus, 

 Cymindis, 

 _ Pandion, 



