On the Affinities of the Falconidce. 323 



the external longer than the internal. Claws large, much 

 covered and pointed ; the hind one much the largest. Type — 

 Falco Bengalensis, Edinburgh Royal Museum. From the 

 characters now given, it is evident that the genus Hierax 

 presents many characters in common with the genus Cerch- 

 nis ; but others again, as the short wings, and scutellated 

 tarsus, lead us on to the next group, or Harpagus, which 

 may be thus characterised ; — Bill short, curved from its 

 base, compressed, but convex, and bulging out laterally as in 

 Hierax ; cutting margin of upper mandible furnished with 

 two teeth, the one a little anterior and above the other ; from 

 the second tooth the hook of the bill makes a very oblique 

 descent. Under mandible furnished with a single notch, and 

 truncated as in the other genera mentioned. Nostrils 

 rounded, and inserted in the cere, which has the same form 

 as in the genus Falco. Loral region partially covered with 

 bristly hairs. Wings very short, not reaching within two 

 and a half inches of the tip of the tail First quill feather 

 very short, third and fourth longest, fifth longer than the 

 second, which is much longer than the first. Tarsus of mo- 

 derate lengthy a small part of its tibial end feathered, the 

 remainder covered with broad quadrilateral scutellae. Toes 

 scutellated. The scutellated tarsus and short wings of this 

 genus at once lead us on to the next division, or genus As- 

 tur, which is thus characterised ; — Bill short, curved from 

 the base, and much compressed laterally ; cutting edge of 

 upper mandible furnished with a festoon, cutting edge of 

 under mandible smooth, truncated obliquely at the tip. 

 Gape extending to the middle of the eye. Cere broad and 

 naked. Nostrils oval, and inserted into the upper, lateral, 

 and fore part of the cere. Plumage rather loose ; wings 

 short and rounded, reaching as far down as the upper third 

 or middle of the tail. Fourth primary quill feather the 

 longest ; third and fifth equal, and nearly as long as the 

 fourth ; first much shorter than the second, which is inter- 

 im u 



