The size and strength of the bill induced us, some years ago, to adopt the popular classification of this genus with the family of Shrikes; but a more particular analysis of that and the neighbouring families, lead us to suspect that its natural situation is far different: our reasons for this belief will be stated at large in another work. For the present it may be remarked, that the smoothness of the rictus, as indicating a frugivorous habit, forbids us to place it with the Flycatchers; while the feet, perfectly different from those of the true Shrikes (_Laniana_, Sw.), can only be compared with those of the _Piauhau_ (Buff.). The affinity which this group bears to _Gubernetes_, is merely superficial: but its analogies to _Ceblepyris_, among the _Laniadæ_, and to _Pachycephala_, among the _Ampelidæ_, are probably direct.
The merit of having first directed the attention of Ornithologists to the singular spurious quill, which generally distinguishes the males of this group, we transfer from ourselves to Azara. His invaluable work we did not then possess, and knew not that the circumstance had already been mentioned by him.
We are only acquainted with the genus _Pachyrhynchus_ of Spix, by seeing this name affixed to our _Psaris Cuvierii_ in the Paris Museum. The distinction is judicious; particularly as the two groups point to different relations. Of _Psaris_, as now restricted, we know of six species, and of _Pachyrhynchus_, ten.
Our present bird is osculent between these forms: we place it with _Psaris_ on account of its wings and tail; but it accords with _Pachyrynchus_ in the rictus being slightly bristled. The spurious quill is half the length of the first, which latter is as long as the fourth. The tail is in a slight degree rounded. It is, perhaps, needless to remark, that all these birds are confined to Equinoctial America.
_Bill_ entire, the sides much compressed, the culmen arched. The lower mandible recurved at the tip. _Wings_ very long. _Tail_ scansorial, the extremity of the shafts naked, and acute. _Tarsi_ naked, the three anterior toes and claws nearly equal; hind toe not versatile. _Nob._
_Brown: wings and tail glossed with greenish blue; back grey-white: chin and under tail covers snowy; tail even._