220 Proceedings of the Biological Society of Washington. 



Rhynchocyclus marginal us flavotectus (Hartert). 1 



Rhynchocyclus megacephala flavotecta Hartert, Novit. Zool., IX, 1902, p. 



608 (.San Javier type locality, and Paramba, N. W. Ecuador). 

 Range: Western Ecuador (San Javier; Paramba; Esmeraldas; Guayaquil, 

 etc.). 



Rhynchocyclus megacephalus (Swainson). 



Tyrannula megacephala Swainson, Bds. Brazil & Mexico, 1841, p. 47, no 

 locality given (Prov. Sao Paulo, S. Brazil). 2 



Range: Southern Brazil (Sao Paulo; Parana); southeastern Paraguay 

 (Puerto Bertoni); extreme northeastern Argentina (Rio Siguendo; Alto 

 Parana, Misiones). 



Characters. — "Upper parts very dusky dull olive green, the feathers of 

 sides of crown with dark centers, as a result of which two distinct blackish- 

 brown stripes are formed, extending from the forehead to back of crown. 

 Lores and narrow superciliary stripe olive-yellowish; sides of head olive- 

 greenish, lined with yellowish. Lesser wing coverts olive green; the middle 

 and greater coverts dark brown with broad reddish yellow ends, which form 

 two distinct cross bands. Remiges dark brown; the primaries with reddish 

 yellow outer borders (the color somewhat paler than the tips of the wing 

 coverts). Rectrices dark brown, with olive-yellow-green outer borders. 

 Throat and fore-neck dull olive-yellowish green; rest of under parts olive 

 yellow. Bill dark horn brown; lower mandible with exception of tip whit- 

 ish. Wing 65; tail 60; bill 15 mm." 



"Another specimen from Matto Dendro, Sao Paulo, is somewhat lighter 

 olive green above; the under parts brighter olive yellow; the fore-breast 

 scarcely washed with olive-greenish, and size decidedly smaller. Wing 59; 

 tail 53; bill 15. It is probably a female." (Free translation from Hellmayr, 

 Verh. zool.-bot. Gesell. Wien, liii, 1903, p. 206.) 



The specimens described above, collected by Natterer, are preserved in 

 the Vienna Museum. They are believed by both Hellmayr and Berlepsch 

 to be the form that Swainson's plate is intended to portray. 



Rhynchocyclus poliocephalus poliocephalus Taczanowski. 3 



Rhynchocyclus -poliocephalus Taczanowski, Orn. Perou, ii, 1884, p. 285 

 (Nauta, N. E. Peru). 



1R. m. flavotectus (Hartert) is similar to R. m. marginatus, but differs in its plain gray 

 crown; more yellow throat and breast (throat grayish on chin only) ; edgings of wing coverts 

 narrower. I have not seen this form, but have followed Chapman (Bull. Amer. Mus. Nat. 

 Hist., XXXVI, 1917, p. 436, in text) in considering it a race of marginatus. It is given as 

 a form of megacephalus by Hartert & Goodson and of sulphurescens by Berlepsch (Proc. IV 

 Int. Orn. Congr. London, 1905 (1907), p. 482). 



2Type locality Prov. Sao Paulo proposed by Hellmayr (Verh. zool.-bot. Gesell. Wien, 

 liii, 1903, p. 206). 



sCharacters. — Cap slaty, mixed with olive green; back brighter green; under parts 

 nearly uniform olive-yellow, somewhat paler and slightly tinged with greenish on the throat 

 and fore-neck. Wing 52-55 mm.; tail 42-45 mm. 



This group, R. p. poliocephalus, R. p. sclateri and R. p. klagesi, may be readily distinguished 

 from representatives of sulphurescens by their smaller size (wing always less than 60). I 

 have not seen specimens of typical poliocephalus poliocephalus. 



