714 BULLETIN 50;, UNITED STATES NATIONAL MUSEUM. 



Mclittarchiis crassirostris Cabanis, Journ. fiir Orn., 1855, 478. 



M[dittarchus] crassirostris Cabanis and Heine, Mus. Hein., ii, 1859, 80, footnote 



(Mexico). 

 [Melittarchus] crassirostris Heine and Reichenow, Nom. Mus. Hein. Orn., 1890, 



147 (Mazatlan). 

 Megarhyyichus crassirostris Finsch, Abh. Nat. Bremen, 1870, 329 (Mazatlan). 



Genus MUSCIVORA Lacepede. 



Musdvora Lacepede, Discours du Coiirs d'Hist. Nat., 1799, 5. (Type, as fixed 

 by Fisclier, Zoognasia, i, 1813, 54, Muscicapa forficata Gmelin.) 



Milvulus SwAiNSON, Zool. Journ., iii, July, 1827, 1G5. (Type, Tyrannus savanna 

 Vieillot, = Muscicapa tyrannus Linnaeus. ) 



Despotes Reichenbach, Av. Syst. Nat., 1850, pi. 6G. (Type, Muscicapa tyrannus 

 Linnseus.) 



Medium sized Tyrannidje (wing about 104-130 mm.), similar in 

 structure to the smaller-billed species of Tyrannus, but tail exces- 

 sively forked, the lateral rectrices much longer than the wing and 

 more than twice as long as middle pair. 



Bill decidedly shorter than head, moderately broad and depressed 

 basally, its width at frontal antise equalto half the length of exposed 

 culmen(in M. forficata) or much more (M. tyrannus) , sthout one and 

 a half times its depth at same point, the vertical profile wedge- 

 shaped, with straight lateral outlines; exposed culmen nearly as 

 long as tarsus (in 31. for'ficata) or only as long as middle toe with- 

 out claw (AL tyrannus), rather indistinctly ridged (especially in M. 

 forficata), straight for most of its length, rather abruptly decurved 

 terminally, the tip of maxilla distinctly uncinate; gonys much 

 longer than mandibular rami, faintly convex; maxillary tomium 

 nearly straight, distinctly notched subterminally. Nostril partly 

 exposed, rather small, obliquely broadly oval. Rictal bristles 

 strong but rather short; feathers of latero-frontal antia^ with very 

 distinct bristly tips, arching over and extending much beyond 

 nostrils; malar antia? wath distinct antrorse or semierect bristles; 

 feathers of chin with (or without?) minute recurved bristly tips. 

 Wing long and pointed, the longest primaries exceeding distal sec- 

 ondaries by one-third to two-fifths the total length of wing; ninth, 

 or seventh, eighth, and ninth, primaries longest, the tenth (outer- 

 most) longer than seventh (or else the latter as long as eighth and 

 ninth) ; eighth, ninth, and tenth primaries (in M. tyrannus) , or 

 tenth primary alone (in M. forficata), abruptly attenuated ter- 

 minally. Tail longer than wing and deeply forked (excessively 

 so in adult males), the lateral rectrices more than twice (sometimes 

 more than four times) as long as middle pair, the latter shorter 

 than distance from bend of wing to end of distal secondaries (nearly 

 as long in M. tyrannus). Tarsus slightly more than one-seventh 

 as long as wing, stout, its scutellation typically exaspidean, the 



