196 Proceedings of the Biological Society of Washington. 



Myiarchus ferox venezuelensis (not of Lawrence) Cherrie, Mus. Brooklyn 

 Inst. Sci. Bull., II, 1916, 244, part (Ciudad Bolivar, Venezuela). 



Description. — Above dark olive; pileum subcrested, with darker centers 

 to the feathers; upper tail-coverts tinged with rusty; auricular region tinged 

 with brownish; wings brown, with sHght paler outer edgings, more promi- 

 nent and whitish on the inner secondaries, the middle and greater coverts 

 edged and tipped with grayish brown, forming two indistinct wing-bands; 

 tail deep brown, the rectrices with obscure external edgings of rusty brown, 

 the outermost pair with narrow buffy white external margins; throat and 

 breast pale neutral gray; abdomen and under tail and wing-coverts prim- 

 rose yellow, much tinged with olivaceous laterally and anteriorly; tibiae 

 duU brown; bill above brown (in skin), paler below; feet black; "iris seal 

 brown" (Cherrie). 



Measurements. — Female (four specimens) : wing, 88-90 (average, 89) ; 

 tail, 81-84 (82.5); bUl, 16-18 (16.8); tarsus, 19.5-20 (19.7). (No adult 

 males seen). 



Range. — Northern Venezuela and Guiana, south to Rio Grande do Sul, 

 southern Brazil. 



Remarks. — In immature dress, represented by several specimens, the 

 crissum is washed with buffy cinnamon, and the remiges and rectrices are 

 more or less broadly edged with rusty cinnamon, as in other species of this 

 group. Of the series of five specimens from the type-locality, the type 

 itself is the only fuUy adult bird. 



This species has nothing to do with M. ferox venezuelensis, with which it 

 has been carefully compared, being much paler, dingier, duller, and more 

 greenish yellow below and under the wings; the gray of the throat and 

 breast is not abruptly defined posteriorly, but merges gradually into the 

 greenish yellow color and tinges it for a considerable distance, especially on 

 the sides, giving a shaded olivaceous effect; the back is of a purer olivaceous, 

 with the head merely a little browner, the ear-coverts the same ; there is no 

 grayish color about the eyes or lores; the bill, too, is shorter, weaker, and 

 paler in color. Moreover, the wing-formula is entirely different, the tenth 

 (outermost) primary being nearly equal to or even longer than the fourth, 

 instead of decidedly shorter, while the tail is always decidedly shorter than 

 the wing. In all its proportions M. sordidus thus resembles M. pelzelni, 

 but differs in being very much darker colored throughout. 



At the time this form was described it was supposed to be confined to a 

 restricted area in northern Venezuela, but such proves not to be the case. 

 Additional specimens have turned up in the collections of other institutions, 

 not only from the Orinoco region and British Guiana, but also from the 

 lower Amazon Valley (Santarem to Pard), and even from the States of Sao 

 Paulo and Rio Grande do Sul, southern Brazil. As this extensive range 

 embraces territory in which M. pelzelni is also found, they must be distinct 

 species, although related. It is true that pelzelni varies considerably in 

 color, but the specimens here referred to sordidus are obviously out of place 

 in a series of that species, while agreeing fairly well among themselves. At 

 the same time additional material from Brazil is very desirable in order to 



