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lowland examples. In the shade of the upper parts I cannot discover any constant 

 difference between the two series. Adult Roraima birds are by no means lighter 

 rufous brown than those from Bartica Grove or Supernaam, and for the present I am 

 unable to discriminate more than one form in British Guiana. 



Thus, T. c. griseigula may be characterised as being similar to T. c. coraya, 

 but as a rule easily distinguishable by the ochraceous or ochreous brown colour 

 of the lower parts, though occasionally specimens may be found which closely 

 resemble the typical race. 



Nomenclature. The earliest available name is apparently Formiciwra 

 griseigula, founded upon an immature example from British Guiana. The de- 

 scription leaves no doubt as to its identity, which, moreover, has been confirmed by 

 Dr. J. A. Allen through examination of the type specimen. 



3. Thryothorus coraya herberti Ridgw. 



Thryothorus herberti (Hiker MS.) Ridgway, Proc. U.S. Mus. x. 1887, p. 516 (1888. Diamantina, 



near Santarem, Lower Amazons) ; Chapman and Riker, Auk, vii. 1890, p. 266 (Diamantina). 

 T. coraya herberti Hellmayr, Journ.f. Orn. 51. 1903, p. 533 (part.: Cara-raucu). 

 T. coraya (errore) Pelzeln, Zur Orn. Bras. i. p. 48 (part : Cara-raucu, Lower Amazons). 



Hab. North Brazil, south bank of the Lower Amazons : Diamantina, near 

 Santarem (Riker), Cara-raucu (Natterer). 



Adult. Nearest to T. coraya coraya, from Cayenne and Manaos, but differs 

 by having the sides of the head almost uniform black (relieved only by a very 

 narrow, inconspicuous, white superciliary streak and a few extremely narrow lines 

 of the same on auriculars) ; the upper parts much brighter, more chestnut rufous ; 

 the light tail-bands cinnamon-brown instead of dull greyish ; the foreneck and 

 chest more purely buffy grey without brownish suffusion ; and the flanks less 

 extensively as also paler rufescent brown. 



Material. One < ad. from Cara-raucu, Lower Amazons, J. Natterer coll., 

 Vienna Museum. Wing 62 ; tail 58 ; bill 16 J mm. 



Observations. This specimen agrees very well with Mr. Ridgway's description, 

 and appears to be decidedly distinct from T. c. coraya. The pileum and nape are 

 dull sepia brown, slightly tinged with umber or rufescent, the remaining upper 

 parts, including wing- and tail-coverts, bright chestnut rufous. Underneath it 

 resembles the Cayenne form, but the breast is somewhat paler and lacks the 

 brownish suffusion, while the flanks are lighter brown. There is, however, no 

 difference between the two races either in size or in the shape of the bill. From 

 T. coraya amazonicus, of Upper Amazonia, T. c. herberti may be distinguished by 

 the reduction of the white markings on sides of head, by the cinnamon-brown 

 (instead of dull greyish) tail-bands and by the bright chestnut-rufous upper parts. 

 Seen from below the two races are perfectly alike. 



4. Thryothorus coraya, amazonicus Sharpe. 

 Thryothorus amazonicus Sharpe, Cat. B. Brit. Mus. vi. p. 235, tab. 15 t fig. 1 (1881. Saraya$u, 



Ucayali, Eastern Peru) ; Berlepsch, Journ.f. Orn. 37, 1889, p. 293 (Yurimaguas). 

 T. coraya amazonicus Hellmayr, Journ.f. Orn. 51, 1903, p. 533 (crit. : Yurimaguas). 

 T. coraya (errore) Sclater and Salvin, P.Z.S. Lond. 1866, p. 178 (part. : Sarayac.u) ; iidem, I.e. 



1873, p. 257 (part. : Sarayacu) : Taczanowski, P.Z.S. 1882, p. 5 (Yurimaguas). 



Hab. Northern Peru, south of the Maraiion : Sarayagu, Ucayali R. (Bartlett) ; 

 Yurimaguas, Huallaga R. (Stolzmann, Garlepp). 



Adult. Much like T. c. coraya, and only distinguishable by its lighter, rufous- 

 brown upper parts and less rufescent-brown flanks. The bill is by no means 



