466 Zoological Society. 



for this species. His single example was obtained in the vicinity of 

 New Friburg in the province of Rio de Janeiro. Those in the British 

 Museum and my own collection have the ordinary appearance of 

 Brazilian skins, and are probably from Rio or Bahia. 



I do not know what has induced Prof. Burmeister to attempt to 

 change Cabanis's correctly formed generic term Dysithamnus into 

 Basythamnus ; but in this, as in other instances, that author seems 

 to undervalue the principle of priority, now universally recognized 

 in the application of names in Natural History. 



1 1 . Thamnophilus melanothorax. 



Supra intense castaneus, remigibus alarum intus nigricanti-hrun- 

 neis, lateribus capitis et corpore subtus ad imum pectus atris, 

 hoc colore in ventrem sensim dilutiore : ve?itre et lateribus oli- 

 vascenti-brunneis rufo tinctis : cauda unicolore castanea : rostro 

 corneOy pedibus nigro-fuscis. 

 Long, tota Q'b^ alae 3" 2, caudse 2*8. 

 Hab. In America Meridionali ? 

 Mus. Brit. 



I have never met with but the single example of this curious bird 

 which is in the British Museum. The genus Thamnophilus is the 

 only one I know of in which it can be placed ; but the bill is more 

 conical and thicker and rather shorter than in the birds of that 

 group, which most nearly approach it in size. There are two white 

 spots on the outer secondaries of the specimen, but these are evi- 

 dently the results of an incipient albinism. 



12. Thamnophilus melanoceps. 



Thamnophilus melanoceps, Spix, Av. Bras. ii. pi. 39. fig. 1. p. 28. 



Ferrugineo-rufuSi subtus clarior : capite toto undique et collo 

 supero nigris : rostro et pedibus nigris. 



Long, tota 7*0, alsB 3*2, caudse 2 '4. 



Hab. Eastern Peru, Saraya9u on the Ucayali (Cast, et Bev.), 



Mus. Paris. 



I was not acquainted with this fine species of Thamnophilus when 

 I wrote the article on the arrangement of those birds in the ' Edin- 

 burgh N. Phil. Journal.* I have since seen several examples in the 

 Museum of the Jardin des Plantes, which were obtained by MM. de 

 Castelnau and Deville at Saraya9U on the Ucayali. The irides are 

 marked " orange." 



Description of a New Species of Antelope (Oryx Bea- 

 trix) FROM Bombay ?, lately living in the Mena- 

 gerie of the Society. By Dr. John Edward Gray, 

 F.R.S., F.L.S., V.P.Z. & Ent. Soc. etc. 



G 



The African genus Oryx is divided into two sections, according 

 to the form of the horn. In one, the Kookaam, or Gemsboc (O. 



