482. PROCEEDINGS OF THE NATIONAL MUSEUM . VOL. 97 
1 im. o&, Venezuela, Brazo Casiquiare, Buenos Aires, February 21, 1931. 
10 ad. &, 10 ad. 9, lim. o&, 1 im. 9, Venezuela, Cerro Yapacana, Upper 
Orinoco, March 20—April 25, 1931. 
This fine series is identified in accordance with Zimmer’s contention 
(Amer. Mus. Nov., No. 703, 1934, p. 4) that duidae is a recognizable 
race distinct from lepidonota, of which form only one specimen 
(a cotype), has been available for comparison. There is no appreci- 
able difference between birds from the Rio Negro and the Brazo 
Casiquiare, on the one hand, and the Cerro Yapacana area on the 
Upper Orinoco on the other. Zimmer found that while duidae ranged 
from the western base of Mount Duida on the Rio Cucucunuma 
southward to the Casiquiare and to the Rio Negro, eastward to the 
vicinity of Santa Isabel, he recorded specimens from the Upper 
Orinoco (Nericagua) as typical poecilinota. Inasmuch as _ these 
Nericagua birds are poecilinota and our Yapacana birds are certainly 
duidae, and inasmuch as the two localities are only a little over a 
hundred miles apart, it would seem that we might have to return to 
the old specific concept that poecilinota is one species with a gray- 
breasted, gray-bellied female, and lepidonota is another (with duidae 
as a race) with a rufescent-tawny breasted and bellied female. The 
difference in the females is very great; the males are very similar. 
This is a condition of frequent occurrence, referred to by Hellmayr 
as “heterogynism,’”’ and need not be interpreted as an indication of 
conspecificity. 
Through the kindness of Dr. Zimmer his series from Duida and 
Nericagua has been made available for comparison with our birds. 
There is no question that the present birds are of the same form as 
his duidae material. In the area to the south and southeast of Mount 
Duida the birds show a slight tendency to vary in the direction of 
duidae, although more of them are nearer to that form than to poecili- 
nota and most of them are definitely typical poecilinota. The two 
probably meet somewhere near Nericagua, but it is quite possible 
that they may be found to overlap, in which case there would be no 
argument about the specific distinctness of the two. 
MYRMOTHERA CAMPANISONA DISSORS Zimmer: Zimmer’s Ant-pitta 
Myrmothera campanisona dissors ZimmEeR, Amer. Mus. Nov., No. 703, 1934, p. 11 
(Rio Casiquiare, Venezuela, right bank, opposite El Mercy). 
SPECIMENS COLLECTED 
2ad. @, Brazil, Rio Maturacd, November 9-12, 1930. 
lim. o’, lad. 9°, Brazil, Salto do Hud, Rio Maturacd, November 20-25, 1930. 
lad. o&, Brazil, Serra Imeri, near Salto do Hud, December 6, 1930. 
1 ad. o’, Venezuela, Chapazon, Brazo Casiquiare, January 31, 1931. 
lim. 9, Venezuela, Brazo Casiquiare, below Cafio Caripo, February 22, 1931. 
