BIRDS OF NORTH AND MIDDLE AMERICA 431 



primaries (from outside) longest, the first shortest, the third about as 

 long as tenth, the first scarcely more than half as long; inner webs of 

 seven outer primaries shallowl}^ sinuated (the sinuation very slight or 

 barely perceptible on seventh). Tail relatively long (more than three- 

 fourths as long as wing), truncate, the rectrices very broad. Tarsus 

 exceedingly robust, about one-fifth as long as wing, its diameter equal 

 to one-fourth its length, or more, nearly the upper half covered in 

 front with dense short feathers, the remainder with exceedingly irreg- 

 ular scales and scutella, generally small and approximately hexagonal 

 in form, but on acrotarsium forming a short series of about 10 broad 

 transverse scutella, and on the planta tarsi much larger, but very 

 irregular both in size and arrangement, forming a somewhat inter- 

 rupted and in places double series, which on the lower portion is 

 twisted to the outer side; middle toe more than half as long as tarsus, 

 the lateral toes much shorter, reaching to about base of third phalanx 

 of middle toe, the outer toe very conspicuously weaker than the inner, 

 the hallux very robust, about equal in length to lateral toes; upper 

 surface of toes with prominent broad transverse scutella except on 

 basal phalanges; claws of hallux and inner toe exceedingly large and 

 strongly curved, but rather obtuse, about equal in length to the digits, 

 the middle claw much smaller, the outer only about one-third as long 

 as the inner. 



Plumage and coloration. — Plumage in general full, the feathers soft 

 and broad with gently convex tips; loral region scantily covered with 

 short bristlelike feathers; feathers of posterior portions of head and 

 neck greatly developed, forming an erectile encirchng ruff, those of 

 the occiput much elongated, forming an erectile crest of rather rigid 

 broad plumes with rounded tips; feathers of thighs short and dense 

 or compact, continued downward in an angle over upper half of 

 acrotarsium. Adults with upperparts and chest plain blackish, the 

 remaining underparts white, the thighs barred with black, the head 

 and neck grayish, the tail crossed by alternate bands of black and 

 mottled grayish; young grayish above, marbled with blackish, the 

 head, neck, and underparts whitish. 



Range. — Continental tropical America. (Monotypic.) 



HARPIA HARPYJA (Linnaeus) 



Harpy Eagle 



Adult (sexes alike). — Forehead, crown, supraloreal and supraorbital 

 areas, cheeks, auriculars, chin, and throat pale smoke gray to smoke 

 gray; the occipital crest darker, dark neutral gray to blackish slate, 

 lores and circumorbital area bare; interscapulars, scapulars, back, 

 rump, wings, and upper tail coverts black with a shght bluish cast, the 

 feathers of the lower back, rump, and upper tail coverts narrowly 



