226 FORMICARIID. 
comes much better in Myrmelastes near Gymnocichia. ‘The tarsi are too long for 
Thamnophilus, and they are covered at the back by a single shield, and not a number 
of scutella, as in Thamnophilus. The feathers of the front portion of the head are 
thin and scattered, showing a tendency towards the bare head of Gymnocichla. The 
frontal feathers of Pyriglena are full and dense, but Gymmnocichla is not distantly 
related to that genus, in which Mr. Sclater originally located the female when he 
described it as Pyriglena ellisiana °®. 
2. Myrmelastes lawrencii. 
Myrmelastes corvinus, Lawr. Ibis, 1863, p. 182° (nec Thamnophilus corvinus, Gould) ; Ann. Lyc. 
N. Y. viii. p. 7”. 
Gymnocichla nudiceps, Salv. P. Z.S. 1870, p. 195 (partim) *; 1874, p. 317%. 
Thamnophilus immaculatus, Scl. Cat. Birds Brit. Mus. xv. p. 189 (partim) °. 
Niger, unicolor, macula celata dorsali et tectricibus alarum apicibus anguste albis: rostro nigro, pedibus 
obscure corylinis. Long. tota 6-U, ale 3-0, caude 2°45, rostri a rictu 1:0, tarsi 1:15. (Descr. maris ex 
Mina de Chorcha, Panama. Mus. nostr.) 
© adhuc nobis ignota. 
Hab. Panama, Chiriqui®, Mina de Chorcha (Arcé), Lion Hill (M*Leannan 12), 
Mr. Lawrence’s Myrmelastes corvinus was placed by Mr. Sclater, following Salvin 4, 
as a synonym of Gymnocichla nudiceps*, but a re-examination of the question makes 
us believe that this is not its true position. On carefully comparing all our specimens 
called Thamnophilus immaculatus and Gymnocichla nudiceps we tind two adult males 
agreeing with one another, and differing in several particulars from both those birds. 
There is no white margin towards the base of the wing as in 7’. immaculatus, and the 
lesser wing-coverts are edged with white and not black as in that bird; moreover, they 
are smaller, and have a shorter tarsus. From G. nudiceps they differ in having the 
crown feathered, the forehead alone showing scanty feathering; the wing-coverts have 
less white, the larger ones being wholly black. 
Mr. Lawrence's description’ was based upon a young male in changing plumage, 
the wing-coverts being tinged with rufous; except so far as this rufous colouring goes, 
our adult birds agree very closely with the type, which, through the kindness of the 
authorities of the American Museum of Natural History, is now before us. 
The peculiarities of this bird are best recognized by placing it in Myrmelastes, and 
by removing Thamnophilus immaculatus to the same genus. These two birds, with 
some others, thus form a genus allied to Gymnocichla in which the feathers of the 
forehead and lores are so thin as to allow the skin beneath to be seen. This feature 
is a step in the direction of the bare head of G. nudiceps, G. chiroleuca being some- 
what intermediate. . 
It unfortunately happens that Mr. Lawrence’s name clashes with Gould’s Thamno- 
philus corvinus, a synonym of T. leuconotus, which we now remove from Thamnophilus 
