NO. 4 DIAGNOSES OF SOME NEW GENERA OF BIRDS — RIDGWAY 3 



long as wing, its upper portion more extensively feathered in front 

 (for one-half instead of only one-third, or less, the length of tarsus), 

 the naked portion of acrotarsium with much fewer (about 7 instead 

 of 12-13) tran'sverse scutellae ; cere much narrower across top, and 

 coloration radically different, the adults and young being conspicu- 

 ously different, the former mostly plain brownish black or blackish 

 brown, the latter with under parts buff or light ochraceous conspicu- 

 ously striped with dusky. 



Also resembling somewhat the smaller species of Buteo, especially 

 B. hrachywtis (which it resembles more in coloration than in struc- 

 tural details), but these differ in (i) having the wing-tip (distance 

 from tip of distal secondary to that of longest primary) equal to 

 much more than one-third the length of wing; (2) only three outer 

 primaries with inner webs emarginated ; (3) first (outermost) pri- 

 mary equal to eighth (instead of equal to tenth) ; (4) tarsus less 

 than one-fourth as long as wing (instead of more than one-fourth 

 as long), and also in possessing several of the characters distinguish- 

 ing Rupornis from Percnohierax. 



(HepKvoi:, dark-colored, dusky; 'lipa^, a hawk. 



Species: Percnohierax lencorrhous (Ouoy and Gaimard). 

 (Monotypic.) 



HAPALOCREX gen. nov. (Rallidae) 



Type : Rallus Haviventris Boddaert. 



Very small Rallese (wing about 66-69 mm.) with longest feather 

 of alula falling short of tips of longest primary coverts ; bill nearly 

 as long as head; toes very long (the combined length of first two 

 phalanges of middle toe as long as tarsus, the hallux, without claw, 

 half as long as tarsus), and with a white superciliary stripe and 

 black loral stripe. 



('ATraAos, delicate; Kpi^, a crake.) 



Species: Hapalocrex Haviventris (Boddaert). (Monotypic.) 



LIMNOCREX gen. nov. (Rallidae) 



Type : Porsana cinereiceps Lawrence. 



Small Rallese (wing about 70-78 mm.) with longest feather of 

 alula extending decidedly beyond tips of longest primary coverts ; 

 nostril narrowly elliptical ; tarsus shorter than middle toe without 

 claw (but longer than combined length of first two phalanges of 

 middle toe) ; outermost primary as long as (sometimes longer than) 



