SPARROWHAWK STRUCTURE AND HABITS. 65 



form of the foot and length of the toes appear to 

 furnish a tolerable indication of the characteristic 

 propensities of several species in this family, 

 which vary considerably in the different genera. 

 Thus, the kestrel (Falco tinnunculus), a true fal- 

 con as indicated by the prominent tooth in the 

 upper mandible and the dark iris is more nearly 

 allied in its habits and the nature of its prey to 

 the buzzards and harriers (Buteo, Circus, &c.), 

 than to its congener, the peregrine; while the 

 sparrowhawk (Accipiter), which in many particu- 

 lars departs from the type of the true falcon such 

 as in having the upper mandible furnished with a 

 smooth festoon instead of a tooth, in the iris being 

 of a bright yellow, the tarsi slender and elongated, 

 and the wings short and rounded yet approaches 

 the peregrine in its decided predilection for fea- 

 thered prey, as well as in the general fearlessness 

 of its character : but although presenting so many 

 points of difference in external aspect and struc- 

 ture, yet in one important respect these two 

 birds agree; in both, the toes are exceedingly 

 long, and admirably adapted for grasping and 

 penetrating the dense plumage of birds ; while 

 the buzzards and harriers, which, in common 

 with the kestrel, prey chiefly on quadrupeds, 

 reptiles and beetles, and require rather strength 



