820 



On the Affinities of the Ealconida. 



(Morphnus, 

 Accipiter, 

 Astur, 



FalconicUc. 



Milvidse. 



Buteidae. 



Harpagus, 

 Hierax, 

 Cerchnis, 

 I Hero falco, 

 * Falco, 

 Erythropus, 



|* Elanus, 

 I Naiiclerus, 

 ! Milvus, 

 ^ Gypacitos, 



Brevitarsus, 



Pernis, 



' Buteopernis, 

 Ictinia, 

 Buteo, 

 - Circus, 

 Serpentarius, 

 Bacha, 

 Polyborus. 



By this arrangement we divide the genus Falco into 

 several divisions. In the first, we include the Falco com- 

 munis, subbuteo, &c. retaining the generic name of Falco. 

 In the third, the Falco tinnunculus, tinnunculoides, &c. are 

 included, and the generic term Cerchnis, Boie retained. 

 The long wing Falcons, of which the Falco vespertinus 

 may be considered the type, are arranged in the genus 

 Erythropus, and for the Falco bengalensis, and Falco biden- 

 tatus, we have adopted the generic terms Hierax* and Har- 

 pagus,-]- which have already been given by authors. 



We shall now enter more into detail, and point out the 

 characters by which each of the genera is characterized, and 

 also the connexion which they bear to each other, in order 



* Under the genus Hierax, two species are included, viz. the one 

 above mentioned, and another species lately discovered in South Ame- 

 rica, and which has been described in the Proceedings of the Zoological 

 Society of London. 



f Under the genus Harpagus two species are included, and both con- 

 fined to South America. 



