( 267 ) 
The range of P. t. semicinerea is as follows :— 
Lower Amazons: Pari (Wallace, Layard, Snethlage), Prata near Para 
(Hoffmanns) ; Itaittiba, left bank of the R. Tapajéz (Hoffmanns, Snethlage); Rio 
Madeira: Borba, Salto do Girao (Natterer), 8. Isabel (Hoffmanns). 
19. Pachysylvia rubrifrons (Scl. & Salv.). 
Hylophilus rubrifrons Sclater & Salvin, P. Z. S. Lond. 1867. p. 569. tab. xxx, fig. 1 [1867.—“ River 
Amazons (1850) ”—Wallace coll.—sc, Rio Negro *]. 
H. ferrugineifrons (nec Sclater) Pelzeln, Zur Ornith. Bras. ii, 1868. p. 70 (Rio Negro below Santa 
Barbara ; Para).+ 
No. 344. ¢ juv., Calama, 7. viii. 1907. “Iris brown, feet and bill grey.”— 
Wing 57; tail 42; bill 133 mm. 
No. 1009. ¢ vix ad. Maruins, 13. vii. 1908. “ Iris dark brown, feet pale 
_ yellowish grey, bill black, below grey.”—Wing 59; tail 424 ; bill 125 mm. 
No. 1023. Adult (not sexed), Maruins, 16. vii. 1908. “Iris brown, feet pale 
grey, bill grey.”"—Wing 61; tail 44; bill 13} mm. ; 
These specimens present very little variation inter se. I have compared 
No. 344 with the type in the British Museum, and found them identical except that 
in the latter the throat and foreneck are somewhat darker, more buffy brownish, 
less yellowish, and the back of a rather duller green. These slight divergencies are 
certainly due to difference of age, for the type is a very young bird, this being 
proved by the fluffy texture of the nape-feathers and the rusty suffusion of the under 
tail-coverts. In fully or nearly adult birds (Nos. 1028, 1009) the latter are clear 
yellow, the back is rather brighter green, and the throat buffy yellow. 
The figure in the P. Z.S. 1867 is wholly misleading: throat and foreneck 
heing represented as pale ferruginous, while they are buffy brownish in the type, 
the wings being far too rufous, etc. 
P. rubrifrons is most nearly related to P. luteifrons (Scl.), from British 
Guiana and Cayenne, but differs in having the frontal and supraloral stripe deep 
cinnamon-rufous (not dingy ochraceous buff), the upper parts of a clearer green 
(without any brownish shade), the cheeks and ear-coverts decidedly isabelline 
(instead of greyish olive), the tail much brighter russet-brown, the throat much 
more tinged with buff, etc. 
P. ferrugineifrons (Scl.), from Bogotd and Venezuela, also bears a certain 
likeness to P. rubrifrons, but may readily be distinguished by its duller, rafescent 
brown tail, greyish olive cheeks and ear-coverts, whitish throat, greyish white (not 
yellowish) belly, and especially by the rufous colour of the forehead being much 
duller and continued over the crown. 
The range of P. rubrifrons, as known at present, is as follows :— 
North Brazil: Rio Negro (Wallace), below Santa Barbara, Rio Negro 
(Natterer). Rio Madeira t: Calama; Marains on the Rio Machados (Hoffmanns). 
Para (Natterer, Snethlage). 
* The type was certainly obtained on the Rio Negro, for we learn from Travels on the Amazons and 
Rio Negro, 1853, p. 163, that Mr. Wallace arrived at the city of Barra do Rio Negro on December 31, 1849, 
and spent all the year 1850 in explorations on that river. 
+ Although the specimens are no longer to be found in the Vienna Museum, there can be scarcely any 
doubt that they are rather referable to P. rubrifrons, for it is this species that was obtained by 
Mr. Wallace on the Rio Negro, and more recently by Miss Snethlage in the vicinity of Pard. 
t Farther to the west, on the Rio Jurudé, however, P. ferrugincifrons (Scl.) is found. A specimen in 
the Museu Paulista, kindly sent for my inspection by Professor H. v. Ihering, agrees perfectly with the 
series from Bogot4 and the Caura Valley in the Munich Museum, 
