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Bolivia) by its much paler belly, the breast being dull rusty buff, the inner sides 
and flanks light rufescent olive-brown, 
L. modulator griseolateralis replaces L. m. modulator on the right bank of the 
Rio Madeira, ranging eastward as far as Santarem, south bank of the Amazons, 
10. Thryothorus genibarbis genibarbis Sw. 
Thryothorus genibarbis Swainson, Anim, in Menag. p. 322 (1838.—“ Brazil”). 
Thryothorus melanos (nec Vieillot) Pelzeln, Zur Orn. Bras, i. p. 48 (part. : Borba). 
No. 671. o& imm., S. Isabel, Rio Preto, 10. x. 1907.—Wing 63; tail 56; 
bill 18 mm. 
No. 646. ? ad., S. Isabel, 8. x. 1907.—Wing 99 ; tail 56 ; bill 164 mm. 
No. 380. Juv., Calama, 11. viii. 1907.—Wing 59; tail 48; bill 15} mm. 
No. 717. ? pull. 8. Isabel, 19. x. 1907.—Wing 99 ; tail 49 ; bill 14 mm. 
“ Tris red (671), reddish brown (646), brown (380, 717); feet plumbeons (adult), 
brownish black (juv.); bill black, below grey.” 
These birds agree, in size and coloration, with typical ZT. gentbarbis from 
Bahia, except that the pileum and nape are distinctly rufescent brown, instead 
of sooty. An adult male from Borba (Natterer coll.), however, is not different 
on this score. The young bird, in nestling plumage, very closely resembles the 
same stage of 7. coraya (Gm.). | 
T. g. genibarbis ranges from Bahia north to Pari, and westwards to the 
right bank of the Madeira (Borba, Calama, 8. Isabel). 
fll. Thryothorus genibarbis juruanus Ihering. 
Cf, Nov. Zool, xiv. p. 345 (Humaytha). 
Represents the foregoing on the left bank of the Madeira: Humaytha 
(Hoffmanns). It differs by its longer wings and rather paler under parts, yet 
its validity requires confirmation by a larger series. | 
12. Thryophilus albipectus albipectus (Cab.). 
Thryothorus albipzctus Cabanis in Schomburgk, Reisen in Brit. Guiana iii. p. 673 (1848. — 
Cayenne). 
Thryophilus taenioptera Ridgway, Proc. U.S. Nat, Mus, x. 1887. p. 518 (1888.—Diamantina near 
Santarem, Tapajéz). 
Thryothorus leucotis (nec Lafresnaye) Pelzeln, l.c. p. 47 (Salto do Girao, Barra do Rio Madeira). 
“ Thryophilus albipectus subsp.” Hellmayr, Nov. Zool. xiv. p, 345 (Humaytha). 
No. 685. ¢ ad., 8. Isabel, Rio Preto, 12. x. 1907—Wing 67; tail 48 ; 
bill 19 mm. 
No. 460. ¢ ad., Calama, 26. vili. 1907.—Wing 64 ; tail 48 mm. 
No. 872. ? ? juv., Marmellos, 27. xii. 1907.—Wing 61; tail 43; bill 
16} mm. 
“ Tris reddish brown (adult), greyish brown (872) ; feet and bill greyish black, 
lower mandible grey.” | 
The specimens agree, in every detail, with a large series of J. albipectus, from 
Para and Venezuela (Caura Valley), in the Munich Museum. Natterer’s examples 
from Barra do Rio Madeira and Mandos, as well as two adult males from the Upper 
Puris (Bom Lugar, Monte Verde), are rather darker ochraceous below than the 
majority of our Caura and Guianan skins, but some of the latter match them 
exactly. The skins from Humaytha, 8, Isabel, and Calama, on the other hand, 
