138 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 
Genus RHOPOTERPE Cabanis. 
(?) Myrmornis Hermann, Tab. aff. Anim., 1783, 188, 235. (Type, Fourmillier 
Buffon.) @ 
Formicivorus Temmincx, Cat. Syst. Cab. Orn., 1807, 92. (Type, by tautonomy, 
Formicivorus palikour Temminck= Turdus formiciworus Gmelin= Formicarius 
torquatus Boddaert.) 
(?) Urotomus Swainson, Zool. Journ., i, no. 3, Oct., 1824, 302, in text (nomen 
nudum); iii, no. 10, Sept., 1827, 166 (diagnosis, but no species named). 
Rhopoterpe > Capants, in Wiegmann’s Archiv fiir Naturg., xiii, pt. i, 1847, 227, 
337. (Type, Turdus formicivorus Gmelin=Formicarius torquatus Boddaert.) 
Medium-sized Formicariide (length about 130-150 mm.) with 
planta tarsi broadly rounded (not ridged) behind; tarsus only one- 
fourth as long as wing; tail only two-fifths as long as wing, nearly 
even; bill as long as or longer than head (commissure longer than 
tarsus), with mesorhinium broad and flattened basally; coloration 
variegated, with a white or fulvous band across subbasal portion of 
remiges, and outer web of primaries crossed by an oblique sub- 
terminal band of buff or fulvous. 
Bill as long as or longer than head, rather slender, rather broad 
and depressed basally, its width at loral antiz greater than its depth 
at same point and equal to less than half the distance from nostril to 
tip of maxilla; culmen distinctly ridged (except extreme base, where 
broad and flattened), straight for most of its length, abruptly 
decurved terminally, the tip of maxilla moderately uncinate; tomia 
straight, slightly but distinctly notched subterminally; gonys slightly 
convex, rather prominent basally. Nostril exposed, separated rather 
widely from loral feathering, narrow, longitudinal (slit-like) overhung 
by a rather broad convex operculum. Rictal bristles obsolete, and 
feathers of chin, malar apex, loral antie, etc., short, without terminal 
sete. Wing large, very concave beneath, rather pointed, the longest 
primaries projecting considerably beyond secondaries; sixth and 
seventh, or sixth, seventh, and eighth primaries longest, the tenth 
(outermost) three-fourths as long as the longest, the ninth longer 
than secondaries. Tail very short (only two-fifths as long as wing), 
nearly even, the rectrices rather narrow, soft, with subacuminate tip. 
Tarsus shorter than commissure, only one-fourth as long as wing, 
rather stout, distinctly scutellate, the planta rather broadly rounded 
@ The ‘‘Fourmillier” of Buffon comprises thirteen species, belonging to eleven 
recognized genera and four families (Formicariide, Conopophagide, Pittide, and 
Troglodytide). So far as I can determine no one has ever fixed a type, and to do so 
by any other method than the ‘‘process of elimination” would involve an amount of 
time and labor which is not at my disposal. Under the circumstances, I prefer to 
retain the generic name Rhopoterpe, notwithstanding the unquestioned priority and 
pertinence of Formicivorus, leaving the final solution of the question to some one who 
has both the time and taste for such investigation. 
b “sd Gestrauch; tépxw, erquicken.’’ (Cabanis.) 
