92 Mr. Swainson on American Thamnophili. 



Closely allied to the last in size, and in general colouring, the 

 bill however is a little shorter, and the feathers across the back 

 and those on the rump are tinged with obscure fulvous. The 

 wings are brown, the greater are slightly margined with whitish, 

 the latter with dull ferruginous, and the scapular quills with a 

 broad base of white. The tail seems longer than the last, it is 

 roundfed, black, and tipt with white ; all the feathers are pointed 

 at their extremities, and this in so regular a manner, as to appear 

 perfectly natural ; the margin of each has a central line of white, 

 longer, narrower, and less conspicuous than in the last. The 

 tarsi are a trifle longer than in T. ambiguus^ and near a quarter 

 of an inch longer than in ncevius. 



Total length 6, bill |, wings 2^7_^ tail 2f , tarsi -5%. 



Observations. — Inhabits the Catinga (or interior) woods of 

 Bahia : the only specimen I possess is a male. 



Two of the preceding descriptions were drawn up from single 

 birds. I therefore feel much difficulty in forming an opinion 

 whether they are varieties of one species, or distinct in them- 

 selves. The slight variation in their colours (consisting princi- 

 pally in those of the tail) is a matter, in itself, of little conse- 

 quence ; but the difference in the comparative length of their 

 tarsi cannot be so easily reconciled. It may also be observed, 

 that the pointed form of the tail-feathers in T.pileatus, is opposed 

 to the rounded form of those in ncevius and ambiguus. The 

 question is interesting, but cannot, I think, be decided, until 

 more specimens are examined. In the mean time they can either 

 be considered as varieties or species. 



6. Thamnophilus ferrugineus. 

 Rufous crowned Bush-Shrike. 



T,ferrugineo-fuscuSy infra pallide fuhus ; vertice rufo ; alisfus- 

 CIS j maculis dorsum teciriceque ornantibus albis ; rectricium 

 rujorum apicibus obtusis, 



T. ferruginous-brown, beneath pale fulvous; crown rufous; wings 

 brown ; spots on the back and wing covers white : tail fea- 

 thers rufous, the tips obtuse. 



