462 PROCEEDINGS OF THE NATIONAL MUSEUM vou. 97 
lim. ?, Brazil, Serra Imeri, near Salto do Hud, December 6, 1930. 
3ad. #, 1 ad. ¢, Brazil, Sao Gabriel, Rio Negro, January 2-13, 1931. 
lad. 9, Venezuela, Brazo Casiquiare, Chapazon, January 30, 1931. 
lad. o&, Venezuela, Brazo Casiquiare, near Cafio Mabinagui, February 20, 1931. 
4 ad. @, 5 ad. 9, Venezuela, Cerro Yapacana, Upper Orinoco, March 18= 
April 25, 1931. 
One of the Sao Gabriel males and the female from there have a 
concealed white patch on the interscapulars. 
Some of the examples collected in January and in April show signs 
of molt. 
This form ranges from the Rio Negro to the Upper Orinoco and 
to the Caura in Venezuela. 
THAMNOPHILUS MURINUS MURINUS Sclater and Salvin: Mouse-colored Ant-shrike 
Thamnophilus murinus ScutaTER and Savin, Proc. Zool. Soc. London, 1867, 
pp. 750, 756 (Barra do Rio Negro= Mandos, accepted as type locality, Berlepsch 
and Hartert, Nov. Zool., vol. 9, 1902, p. 69). 
SPECIMENS COLLECTED 
2ad. o, lim. 9, Brazil, Cucuhy, Rio Negro, February 7-8, 1930. 
2 ad. o, Brazil, Santa Isabel, Rio Negro, October 9-10, 1930. 
1 ad. 9, Brazil, Rio Negro, mouth of Rio Cauabury, October 21, 1930. 
lad. o&, 2 ad. 9, Brazil, Rio Cauabury, October 28—-November 7, 1930. 
lad. 9, Brazil, Salto do Hud, Rio Maturacd, November 17, 1930. 
lad. o, lad. 9, Brazil, Serra Imeri, near Salto do Hud, December 5-7, 19380. 
3ad. of, lim. &,3ad. 9, Brazil, SAo Gabriel, Rio Negro, December 29, 1930— 
January 16, 1931. 
1 ad. &@, 1 ad. 9, Venezuela, Upper Orinoco, near Isla Temblador, February 
25, 1931. 
1 ad. &, Venezuela, San Antonio, Upper Orinoco, March 9, 1931. 
1 im. o, 2 ad. 9, 1 ad—(), Venezuela, Cerro Yapacana, Upper Orinoco, 
March 30—April 25, 1931. 
One of the April birds was noted as being in breeding condition 
when collected. 
This ant-shrike ranges along both banks of the Rio Negro and 
north to the Upper Orinoco and thence eastward to British Guiana 
and Surinam. Zimmer has noted (Amer. Mus. Nov., No. 647, 1933, 
p. 8) that the British Guiana males are a very little darker than 
typical murinus, thereby slightly approaching cayennensis. Only one 
male from British Guiana has been available for study in the present 
connection, and it fails to bear out this observation agreeing with 
those other specimens noted by Zimmer that are indistinguishable from 
Rio Negro examples. 
THAMNOPHILUS AMAZONICUS CINEREICEPS Pelzeln: Gray-capped Ant-shrike 
Thamnophilus cinereiceps PELzELN, Zur Ornithologie Brasiliens, pt. 2, 1868, p. 
77, 145 (Marabitanas, Upper Rio Negro). 
SPECIMENS COLLECTED 
2 ad.—(1 of, 1 9), lad. 2. Brazil, Salto do Hud, Rio Maturac4é, November 
18-23, 1930. 
