FALCONnXE DIURNAL RAPTORES. 447 



Young female (No. 48,826, Santiago, Chili, May, 1866: Dr. Philippi). Occiput and nape 

 thickly marked with broad streaks of dusky, tinged with rusty; scapulars umber- brown, 

 tipped with rusty; all the feathers of the wings narrowly tipped with white; tail-feathers 

 with a subterminal irregular bar of dark ashy ; breast tinged with rufous, and with badly 

 denned cuneate spots of deeper rusty. Wing, 12.25; tail, 7.50. 



An adult female, obtained at San Francisco, California, Febru- 

 ary 11, 1868, had the "bill black, eyes orange-red, tarsi and toes 

 yellow." Total length 16 inches, extent 42 inches. 



As to the occurrence of this species in Illinois, we have little infor- 

 mation, the only record being that of the writer's previous lists, 

 based on a pair observed near the river at Mt. Carmel during the 

 summer of 1863 or 1864. It is very likely of not uncommon occur- 

 rence during summer in suitable places in the extreme southern 

 counties of the State. 



GENUS ICTINIA VIEILLOT. 



Ictinia VIEILI*. Analyse, 1816, 24. Type, Falco mississippiensis Was. 



Nertus BOIB, Isis, 1828, 314. Type, Falco plumbeus GMEL. 



GEN. CHAE. Form falcon-like; the neck short, shoulders broad, wings long and 

 pointed, the rectrices strong and stiff, claws strongly curved and acute, and general or- 

 ganization robust. Bill short and deep, "bulged" laterally, the terminal hook abruptly 

 compressed; tomia irregularly toothed and notched; gonys very convex, ascending ter- 

 minally. Cere narrow; nostril very small, roundish. Feet small but robust, the tarsus 

 about equal to the middle toe; outer toe decidedly longer than the inner, which is equal 

 to the hallux; web between it and the middle toe well developed; tarsus with a distinct 

 frontal series of broad transverse scutellse; claws short, but strongly curved, very sharp, 

 grooved beneath. Third quill longest; first of variable proportion with the rest; outer 

 two with inner webs sinuated. Tail a little more than half the wing, emarginated, or 

 nearly even, the feathers broad, with nearly truncated, though rounded, ends. 



Structurally, Ictinia seems to be most nearly related to Harpagus, 

 a tropical American genus, which, however, differs much in gen- 

 eral appearance, being of decidedly hawk-like aspect. The struc- 

 tural differences between the two genera may be tabulated as fol- 

 lows: 



Ictinia. Tomial tooth simple. Tarsus nearly equal to, or but little longer than, the 

 middle toe; posterior toe equal to the outer. Wing very long, reaching to or beyond 

 end of the tail, the primaries greatly developed, almost twice the length of the second- 

 aries. Tail about one half the wing, even, or slightly emarginated. 



Harpagus. Tomial tooth double. Tarsus about one and a half times the middle 

 toe ; posterior toe decidedly shorter than the outer. Wing short, reaching only to about 

 the middle of the tail, the primaries only moderately developed, less than one and a half 

 times the secondaries. Tail nearly eq.ua! to wing, slightly rounded. 



