BIRDS OF NORTH AND MIDDLE AMERICA 621 



ff. Smaller; wings 174-189 (183 mm.) (Cuba and Isle of Pines). 



F. sparverius sparverioides, ad. 9 (p. 743) 

 ee. Underparts abundantly streaked with brownish to dark fuscous. 

 /. Ventral streaks very dark, dark fuscous (Puerto Rico and Lesser 



Antilles) F. sparverius caribaerarum, ad. 9 (p- 748) 



//. Ventral streaks paler; Saccardo's umber to pale sepia. 



g. Hazel crown patch very small or wanting (southern Mexico, 

 Guatemala, Honduras). 



F. sparverius tropicalis, ad. 9 (p- 743) 

 gg. Hazel crown patch usually fairly extensive, sometimes very 

 much so, covering most of head. 

 h. Size larger; wings usually 185 mm. or longer (Alaska, Canada, 

 United States, except southeastern States). 



F. sparverius sparverius, ad. 9 (p- 724) 

 hh. Size smaller; wings usually under 185 mm. 



i. Tail shorter, usually less than 120 mm. (southeastern United 



States) F. sparverius paulus, ad. 9 (P- 740) 



ii. Tail longer; usually over 120 mm. (northwestern Mexico). 

 F. sparverius peninsularis, ad. 9 (p- 741) 



Subgenus Gennaia Kaup 



Large falcons (wing about 294-355 mm.) similar in structure to 

 Hierofalco but with outer toe (without claw) slightly longer than 

 inner toe, and with tarsus relatively longer (much longer than middle 

 toe without claw) ; less than upper half of tarsus feathered, the naked 

 space on posterior side much wider. 



Large falcons X^ing about 294-355 mm.) similar to Hierofalco in 

 structural details, but less heavily built, with bill and feet relatively 

 smaller, tarsus much longer than middle toe without claw, with less 

 than upper half feathered in front and with bare space on posterior 

 side much wider, and with outer toe (without claw) slightly but de- 

 cidedly longer than inner toe. 



Bill moderately stout, the culmen (chord) about as long as hallux 

 (without claw) or a little shorter; strongly decurved almost (if not 

 quite) from base, rounded or very indistinctly ridged {F. mexicanus) 

 or distinctly ridged {F. biarmicus, F. jugger) ; maxillary tomium with 

 subterminal "tooth" prominent and immediately preceded (proxi- 

 mally) by a distinct concavity, sometimes followed by a slight con- 

 vexity; gonys more or less convex, ascending terminally, prominent 

 basally, more or less distinctly (but not sharply) ridged on median 

 line; cere moderately broad, almost wholly bare; nostril moderately 

 large, wholly uncovered. Wing long and pointed, the longest primary 

 exceeding distal secondary by decidedly more than half the length of 

 wing; second primary (from outside) longest (the third sometimes 

 nearly as long in F. mexicanus), the first (outermost) equal to or slightly 

 shorter than third {F. biarmicus, F. jugger) ; only the first (outermost) 

 primary with inner web distinctly emarginated {F. Jeldeggi and F. 



