478 ' PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 97 
The male is the type of the species. As stated in the original de- 
scription, the type is in molt, and the incoming adult feathers of the 
wings and back and underparts are similar to those of the immature 
plumage, indicating that the adult male will probably be found to 
resemble the type. The species is not too distantly related to Myr- 
meciza atrothorax but is clearly specifically distinct from that form. 
After examining the present two specimens Dr. Zimmer noted that 
the general plumage has about the texture of Cercomacra carbonaria 
and suggested that it is possible that a fully adult male, if markedly 
different from the type, might show a closer relationship to that genus 
than the present examples demonstrate. The pattern of the markings 
of the upper wing coverts is very like that of some forms of Cercomacra 
(serva, for example), but the bill is that of Myrmeciza. Dr. Zimmer was 
unable to feel certain that the type had been correctly sexed, but this 
cannot be checked. It is unfortunately true that a number of speci- 
mens in the present collection appear to have been wrongly sexed by 
the collectors. 
MYRMECIZA PELZELNI Sclater: Gray-bellied Antcatcher 
Myrmeciza pelzelni ScLtatER, Catalogue of birds in the collection of the British 
Museum, vol. 15, 1890, p. 283 (Marabitanas, Rio Negro). 
SPECIMENS COLLECTED 
1 ad. o’, Brazil, Cucuhy, Rio Negro, February 2, 1930. 
lad. o&,1lim. 9, Brazil, Salto do Hud, Rio Maturacd4, November 24, 1930. 
3 ad. o, 2im. o’, 3 ad. 2, 1 ad. — (o?), Brazil, Serra Imeri, November 26— 
December 2, 1930. 
This is one of the very few birds that appears to be wholly restricted 
to the upper Rio Negro, not having been found yet on the adjacent 
portion of the Amazon or in the basin of the Casiquiare or the Upper 
Orinoco. 
The immature males resemble the adults but have a few whitish 
or grayish feathers mixed in with the black of the breast; the immature 
female differs from adults of its sex in having the white of the throat 
less extensive, more encroached upon by feathers with squamate 
blackish markings, and in having the blackish margins of the pectoral 
feathers deeper, broader, and extending over more feathers posteriorly. 
FORMICARIUS COLMA COLMA Boddaert: Guianan Ant-thrush 
Formicarius colma BoppAErRT, Table des planches enluminéez . . . , 1783, p. 44 
(based on “‘Le Colma, de Cayenne’’ Daubenton, Planches enluminées ... , 
pl. 703, fig. 1: Cayenne). 
SPECIMENS COLLECTED 
lad. 9, Brazil, Cucuhy, Rio Negro, February 7, 1930. 
lad. 9, Brazil, Rio Maturacdé, November 9, 1930. 
lim. o, Brazil, Salto do Hud, Rio Maturacd4, November 22, 1930. 
lad. o&, Brazil, Sio Gabriel, Rio Negro, January 9, 1931. 
