PTILCGONYS. 411 



Tail longer than wings, somewhat fan-shaped, nearly even in type, the slight 

 emargiuation greater than the rounding (in caudatus much graduated, with 

 central feathers prolonged). Feathers hroad, the outer webs very narrow. 

 Wings pointed, although the outer feathers are much graduated ; Ist quill 

 not half the 2d, which is shorter, the 3d rather longer, than secondaries ; 5th 

 and 6th longest ; 1st, 2d, and 3d attenuated and acuminate at end. 



Bill short, much depressed, hooked and notched at both tips ; gape wide 

 and deep ; commissure straight ; culmen for terminal half and short gonys 

 considerably curved. ^Nostrils oval, bordered above and behind by mem- 

 brane, the frontal feathers reaching not quite to the posterior margin ; rictal 

 bristles distinct, but moderate. 



Legs weak ; tarsi very short, less than middle toe and claw, with strongly 

 marked rough scutellae (seven) anteriorly, one or two divisions on the lower 

 part of sides. Outer toe rather longer than inner, and reaching just beyond 

 base of middle claw. Hind claw considerably longer than middle. Basal 

 joint of middle toe adherent for almost its whole length to one and a half 

 joints of outer ; internally for basal half of length to basal half of first joint 

 of inner. 



P. caudatus, very similar otherwise, differs remarkably in structure of tail, 

 which is cuneate and nearly one and a half times the length of tbe wing; 

 the two central feathers greatly prolonged and tapering gently to a rounded 

 narrow tip, the other feathers graduate from these to the outermost. 



Ptilogonys differs from Myiadestes in more compact plumage ; 

 a shorter, broader, tliicker bill ; the frontal feathers much less 

 bristly ; the nostrils broader and more exposed, with a greater ex- 

 tent of naked membrane behind them. The legs are shorter, but 

 stouter ; tarsus much shorter and roughly scutellate, not smooth ; the 

 claws thicker and more curved ; the hinder considerably larger than 

 the middle. Nearly the whole extent of basal joint of middle toe 

 is adherent externally, not the half only ; internally adherent for 

 half to the basal half of first joint of inner, which in Jlyiadestes are 

 divided to base. The wing is much more graduated ; the third quill 

 having tbe relationship to the longer ones that the second has in 

 Myiadedes. The tail lacks the deep emargination of Ilyiadestes ; 

 the lateral feathers are of equal width to near the end, or even 

 wider, instead of becoming narrower. 



There has been much diversity among writers in the spelling of 

 the name of this genus, Mr. Swainson, its author, having himself 

 written it very differently. His first rendering of the name, how- 

 ever — Ptilogonys — is more nearly correct than the subsequent ones, 

 as compounded of n.rt.\ov and yovt., or feathered knee, in allusion to 

 the tuft of cottony feathers on the tibiae. 



The two known species of Ftilogonys are cjuite similar in colora- 

 tion, but differ markedly in shape of tail, which in one is even, in 

 the other greatly cuneate. The characters are as follows : — 



