S54 Mr. Swainson on the Genus Psaris. 



Art. XLI. On the Genus Psaris of M. Cuvier, with an 

 Account of two new Species. By William Swainson, 

 Esq. F.R. 8f L.S. 



The vast influx of new objects continually coming before us, 

 and a better acquaintance with those already noticed by pre- 

 ceding naturalists, has gradually extended the limits of many 

 genera, originally supposed to consist but of one species. The 

 genus Psaris of M. Cuvier remained for some years in this state ; 

 being confined to a single species — the Lanius Cayanus of Lin- 

 naeus ; a second was discovered by myself in Brazil, and has been 

 described (under the name of P. Cuvieri,) in the first volume of 

 Zoological Illustrations ; I am now enabled to augment this 

 group by two other species, very distinct from the preceding, 

 and which seem not yet to have been recorded. 



On closely examining these birds, with the view of ascertaining 

 the leading distinctions which separate Psaris from the neigh- 

 bouring genus Tyrannus^ I have noticed one or two peculiarities 

 which appear to me sufficiently important for this purpose: the 

 following generic characters for the group are therefore proposed. 



PSARIS. 



Fam. Laniad^. Vigors. 



Subfam. Tyrannina. 



Rostrum validum, crassum, rectum, culmine rotundato, mandi- 

 bulae superioris apice adunco, emarginato ; naribus rotundis, 

 nudis, membrana obsoleta ; rictu inermi. 



Alae elongate, remige primo breviore, secundo tertioque longissi- 

 mis ; inter remigem primam et secundam penna brevis, 

 angusta, spuria, interest ; pcgoniis utrinque emarginatis. 



Pedes mediocres, squamis lateralibus numerosis, ovatis. 



Cauda nriediocris, aequalis vel rotundata. 



