52 
ZOOLOGY OF THE VOYAGE OF THE BEAGLE. 
G. R. Gray has pointed out that Commerson had previously considered it the type 
of his genus, Lichenops, we have been induced to prefer the latter as the oldest name. 
It is common in the neighbourhood of the Plata, and across the Pampas, as far as 
Mendoza on the eastern foot of the Andes ; it has not, however, crossed those 
mountains and entered Chile. It usually sits on the top of a thistle, and like our 
common fly-catchers ( Muscicapa grisola), takes short flights in pursuit of insects ; 
but does not, like that bird, return to the same twig. It feeds, also, occasionally 
on the turf : in the stomach of some which I opened, I found Coleopterous insects, 
chiefly Curculionidae. Beak, eye-lid, and iris, beautiful primrose yellow. 
2. Lichenops erythropterus. Gould. 
Plate IX. 
L. supra nigrescenti-brunneus, plumis rufo-marginatis ; primariis secundariisque casta- 
neis, apicibus pogoniaque externa dimidio apicali brunneis ; gutture corporeque 
subtus cervinis ; pectore brunneo-marginato. 
Long. tot. 6 unc. ; alee, 3; caudce, 2-|; tarsi , 1; rostri, 
All the upper surface and tail blackish brown, each feather margined with rufous; 
primaries and secondaries reddish chesnut, their tips and their external webs 
for half their length from the tip, brown ; tertiaries, greater and lesser wing- 
coverts dark-brown, each feather margined with reddish buff; throat, and 
all the under surface, fawn colour ; the chest spotted with brown ; base of 
the bill, and chiefly of the lower mandible, as well as the iris, bright yellow ; 
eye-lid, blackish yellow; feet, dark brown. 
Habitat, Banks of the Plata. 
This bird is not very common. It frequents damp ground, where rushes 
grow, on the borders of lakes. It feeds on the ground and walks. It is certainly 
allied in many respects with the foregoing species, but in its power of walking, 
and in feeding on the ground, there is a marked difference in habits. As it has 
lately been described (Swainson’s Nat. Libr. Ornith. x. p. 106.) as the female of the 
L. perspicillatus, I will here point out some of its chief distinguishing characters. 
Its beak is slightly more depressed, but with the ridge rather more plainly pro- 
nounced. In the L. perspicillatus, the upper mandible is entirely yellow, excepting 
the apex ; in the L. erythropterus, it is entirely pale brown, excepting the base. The 
eyelid in the former is bright primrose yellow, in the latter blackish yellow. The tail 
of L. erythropterus is squarer and contains only ten feathers instead of twelve : the 
wing is to of an inch shorter, and the secondaries relatively to the primaries are also 
shorter. The red colour on the primaries represents, but does not correspond with, the 
white on the black feathers of L. perspicillatus ; and the secondaries in the two birds 
