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. Tt 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 nigrescent i-hninncus,plu)nis riifo-mnrginatis; primariis secuudariis(jue casta- 

 ueis, apicibus pogonia'qne exlernce dimidio apicah bruuneis ; gulture corporeque 

 sublus cervinis ; pectore brunneo-marginato. 



Long. tot. 6 line; alw, 3; cauda; 2^; tarsi, 1; rostri, j^^. 



All the upper surface and tail blackish brown, each feather margined with rufous; 

 primaries and secondaries reddish chesnut, their tips and their external webs 

 forhalf 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 tcalks. 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. perspiciUatiis, 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. perspiciUatiis, 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. erytltropieras is squarer and contains only ten feathers instead of twelve: the 

 wing is A 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 i./w5/«c///a/it5,- and the secondaries in the two birds 



