266 
ROCKY MOUNTAIN ANTCATCHER. 
the Tyrannus hellulus^ Vieill., which, however, is much larger, 
with a still longer tail, differing also by having a large black 
collar extending to each corner of the eye, margining the 
white throat ; and the head of the same bluish-grey colour 
with the other superior parts of the body ; the rernaining under 
parts being of the same colour, with a narrow brown line in 
the middle of each feather ; and by having a whitish line on 
each side of the head behind the eye, extending to the occi- 
put. The Tyrannus hellulus is a native of Brazil. 
ROCKY MOUNTAIN ANTCATCHER MYIOTHERA 
OBSOLETA Pjlate I. Fig. 2. 
Troglodytes obsoleta, Say, in Long's Expedition to the Rochy Mountains, vol. ii. 
p. 4 Philadelphia Museum, No. 2420. 
TROGLODYTES OBSOLETA Say* 
Myiotliera obsoleta, Bonap. Synop. p. 73. 
This bird is one of those beings which seem created to 
puzzle the naturalist, and convince him that nature will never 
conform to his systems, however perfect his ingenuity may be 
capable of devising them. This Avill become sufficiently appa- 
rent, when we consider in what manner different authors would 
have arranged it. 
We cannot positively decide whether Vieillot and his fol- 
lowers would have referred this species to Myrmothera^ a name 
they have substituted for Myiotliera ; to their genus Thryotho- 
rus, which we unite to Troglodytes ; or to their slender-billed 
section of Thamnopliilus^ rejected by us from that genus, and of 
which some recent authors have made a genus called Tormici- 
vora ; yet we have very little hesitation in stating our belief, 
that they would have assigned its place among the species of 
the latter* According to our classification, it is certainly not 
* We pi'efer retaining this bird for the present in Troglodytes, The habits, 
colour and marking, nest and call of this bird, bring it nearer to the wrens. 
There is no question, however, of its being an aberrant form, wherever it may 
rank. — Ed. 
