15. POLTBOKOIDES. 47 



e"". Outer toe about equal to inner 

 toe witliout claw ; thig-hs with 

 overhanging tuft of featliers. 

 aa. NostrUs with bony tubercle 

 near upper margin. 

 aa . Feathering of tarsus extend- 

 ingfurtherdownthanlength 

 of middle toe (without 

 claw) ; tarsus scaled right 

 across, only the, hinder mar- 

 gin of outer aspect reticu- 

 late 20. Erythrocnema, 



hh' , Feathering of tarsus not ex- p. 84. 



tending so far dowu as 

 length of middle toe; tarsus 

 scaled in front, reticulate on 



outer aspect 21. Melierax, p. 86. 



hh. Nostrils oval, with no bony 



tubercle 22. Astuh, p. 92. 



d". Commissure perfectly straight .... 23. Isisoides, p. 129. 

 /". Eidge of bni, measured from anterior 

 margiji of cere, less than half middle 

 toe without claw 24. Accipiter, p. 130. 



15. POLYBOROIDES. „^ 



Type. 

 Polyboroides, Smith, S. Afr. Q. Journ. i. p. 106 (1830) . . P. typicus. 

 Gymnogenys, Less. Traite, p. 64 (1831) P. radiatus. 



Bill of Polyboroides typicus. 

 Baiige. Africa geuerally and Madagascar. 



Key to the Species. 



a. Silver-grey, thinly barred with black below 

 h. Dark grey, thickly barred with black below 



radiatus, p. 48. 

 typicus, p. 48. 



