30 BASSE RES 
and abruptly attenuated towards the tip. The culmen is strongly ridged, but less hooked 
than in Scotothorus and Neopfelma, The notch near the tip of the upper mandible is barely 
indicated. There are scarcely any rictal bristles, always more or less developed in the two allied 
genera, Nostrils situated in a groove, oval and open. In the wing, the fourth primary is the 
longest, the third and fifth are about 1 1/2 mm shorter and equal in length; first remex equal 
to the seventh. The tail is strongly graduated, the outermost rectrix being much shortened 
and at the same time narrowed and pointed. The middle pair, on the other hand, is very broad 
and rounded on the tip. Metatarsus rather short, covered in front with about five scutes. Sexes 
dissimilar, Males with a bright vertical patch. 
Geographical Distribution. Amazonia, the upper Orinoco valley and in southern 
French Guiana. Only four species are known. 
hE OME Das PE Glss 
1. With a bright vertical patch (OS) 
. 2, 
—- No bright vertical patch (Q Q) Shee 
2. Forehead and sides of crown very different jyom the olive green colour of the back . 5 {anon 
— Forehead and sides of crown olive green like the back . 4. 
3. Crown-patch fiery ved, forehead and sides of crown black; throat silky white, breast 
QUESTMUTS Ad toy coe ee) se) ee ee es) eed ee en eee IN REACT Ooe 
— Crown-patch lemon yellow, forehead and sides of crown ashy gray; throat dirty 
white, breast and abdomen pale sulphur yellow. 
ae 
So: .) s = © . 4S UTE OCEPEAT ISH (in)E 
4 Crown-patch golden yellow; breast chestnut brown, considerably darker than the 
abdomen : . H. FLAVIVERTEX. 
- Crown-patch orange; breast and abdomen uniform pale reddish ochreous . H. AURANTIIVERTEX (1). 
5S. Upper parts dull brownish exces.) rst ee) ee) tee cl eeIN DEADUS: 
SOT AULA Oe 8 ll fl Be Jel ANDES ((D)), 
1. Heterocercus linteatus (Strickland). 
Elaenia linteata Strickland, Contr. Orn. 1850, p. 121-15, t. 63 (part. 9) (« upper branches of the Rio Amozons »). 
Hab. North Brazil : Rio Madeira; Monte Alegre on the Lower Amazons; Rio Tapajoz. 
2. Heterocercus flavivertex Pelzeln. (Plate 1, Fig. 6.) 
Heterocercus flavivertex Pelzeln, Zur Ornith. Bras. Abt. 2, p. 186 (1868) (Rio Negro). 
H. angosturae Berlepsch & Leverkiihn, Ornis, Vol. 6, p. 1y (1890) (Orinoco). 
Hab. N. W. Brazil : Rio Negro from the mouth of the Rio Branco upwards ; Venezuela : on the upper 
Orinoco near Maipures and Perico; South Cayenne : Oyapoc (2). 
3. Heterocercus aurantiivertex Sclater & Salvin. 
Aleterocercus aurantiivertex Sclater & Salvin, Proc. Zool. Soc. Lond. 1880, p. 157 (Sarayacu). 
Hab. Only known from Sarayagu, Eastern Ecuador. 
4. Heterocercus luteocephalus (Lesson). 
Muscicapa luleocephala Lesson, Traité d’Orn, p. 392 (1830) (no locality); Pucheran, Arch. Mus. Hist. Nat. Paris, 
Vol. 7, p. 374 (1855) («l’Amérique méridionale »); Hellmayr, Novit. Zool. Vol. 13, 1906, p. 326. 
Hab. unknown. 
(1) The females of H. aurantitvertex and H. luteocephalus are unknown, 
(2) The record from Chamicuros, N. Peru, cannot be located with certainty since only young males were obtained. 
These may belong either to H. flavivertex or to H. aurantitvertev. 
