133 



iii foi-ni to that of the common black cock, the type of Mr. Swain- 

 soh's section. 



The bird above described has every appearance of being adult, 

 and, as far as I have been enabled to ascertain, is from Siberia; it is 

 h'ss in all its proportion than the common species, but has the tail- 

 l'eathers more developed; there are traces of some white feathers 

 about the throat and cheeks, but as the markings thus produced are 

 not regular, I have reason to consider it as accidental. I have given 

 it the specific appellation of Derhianus, in honour of the Earl of 

 Derby, in vvhose collection it is eontained. 



Mr. Gould afterwards exhibited, from his own collection of Au- 

 stralian birds, an entirely new group of four species, for •which no 

 generic title has yet been applied, so far as he was aware, and but 

 one species only characterized, by Messrs. Vigors and Horsfield, 

 under the name of Acantheza frontalis ; for this genus Mr. Gould 

 proposed the generic name of Sericornis, and for the three species, 

 those of citreo-gularis, humilis, and parvultis. 



Family SAXICOLINiE. 

 Genus SERICORNIS. 



Rostrum robustum, rectum, caputąue quoad longitudinem fere 

 aequans, ad apicem compressum, et indentatum. 



Nares basales, laterales, ovales, et operculo tectae. 



AlcB mediocres, rotundatse ; remige primo perbrevi, ąuarto, quinto, 

 atque sexto longissimis et inter se ferė 8equalibus. 



Cauda mediocris et gequalis. 



Tarsi elongati ; digitus posticus cum ungue validus, digitum in- 

 terraedium ferė aequans ; digitis externis aequalibus. 



PlunuB molles et sericese. 



Typus est Acanthiza frontalis, Vig. and Horsf. 



Sericornis humilis. Ser. loro nigrescenti-fusco ; et siiper hoc 

 strigo, indistijictd albd ; vertice, corpore suprd, ali^, cauddątie 

 olivaceis, rubro lavatis; aid spurid nigrescerite ; plumis si/7gulis 

 albo margi7iatis ; gula cinered fusco guttatd; pectore abdomine- 

 que medio, fuscescenti-jlavis, illo fusco indistincte guttato ; late- 

 ribus castaneis; rostro nigrescente ; pedibus fuscis. 



Long. tot. 5 uuc. ; rostri, |; alce, 2|; cauda, 2^; tarsi, 1. 



Hab. Terra "N'an Diemen. 



Sericornis citreogularis. Mas. Ser. loro, annulo circum- 

 oculari, pluniisgue auricularibus intensė nigrescenii fuscis ; linen 

 fiavescente a naribus super oculos excurre?ite; vertice, corporegue 

 suprd, rectricibus, secondariisgite alarutn, caitddgue rufo-brun- 

 neis; primariis ad marginėm externum olivaceis; aid spurid 

 nigrescente ; gula citrina; pectore lateribusąue olivaceo-fuscis ; 

 abdomine medio albo; rostro nigro; pedibus brunneis. 



Long. tot. 5į unc; rostri, |; alce, 2|; cauda, 2§; tarsi, 1^. 



Hab. Nova Cambria Australi. 



