610 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 



h. Smaller and slightly darker, with dusky stripe on inner web of 

 rectrices averaging broader and darker; wing averaging 93 or less 

 in male, 89.8 or less in female. 

 i. Wing averaging 93 in male, 89.8 in female; bill brownish or 

 dusky. (Colombia, Cayenne, etc., to southern Brazil, Para- 

 guay, etc.) Myiarchus tyrannulus (extralimital) « 



a. Wing 86.4-88.9; bill black. (Islands of Curasao, Aruba, and 

 Bonaire, Dutch West Indies.). . .Myiarchus brevipennis (p. 620) '> 

 hh. Larger and paler, with dusky stripe on inner web of rectrices nar- 

 rower and less dark; wing averaging more than 100 in male, 

 more than 94 in female. {Myiarchus mexicanus .) 

 i. Smaller (adult male averaging wing 102.3, tail 93.3, exposed 

 culmen 21.5; adult female, wing 94.8, tail 89.6, exposed cul- 

 men 20.6). (Lower Rio Grande Valley of Texas through 

 eastern Mexico to ELonduras.) 



Myiarchus mexicanus mexicanus (p. 621) 

 a. Larger (adult male averaging wing 108.9, tail 99, exposed cul- 

 men 24.1; adult female: wing 106.5, tail 96.2, exposed 

 culmen 24.3). (Southern Arizona and southward over Pacific 

 slope of Mexico to western Guatemala.) 



Myiarchus mexicanus magister (j). 623) 

 ff. Dusky stripe on inner web of outermost rectrix narrower, occupying 

 much less than one-third the width of the web, except terminally, 

 decreasing gradually in width basally; bill relatively smaller 

 (exposed culmen averaging less than 18). (Western and south- 

 western Mexico; Guatemala in winter.) 



Myiarchus nuttingi inquietus (p. 631) 



ce. Inner webs of rectrices without a distinct (if any) stripe of dusky along 



shaft. 



/. Inner webs of rectrices wholly cinnamon-rufous, or else a very narrow 



streak of dusky along shaft on terminal portion; wing relatively shorter 



(averaging less than 96 in males, less than 95 in females). 



« Muscicapa tyrannulus Miiller, Syst. Nat. Suppl., 1776, 169 (Cayenne). — Myiarchus 

 tyrannulus WTiite, Proc. Zool. See. Lond., 1882, 608 (Argentina); Sclater, Cat. Birds 

 Brit. Mus., xiv, 1888, 251, part (excl. West Indian localities, references, and speci- 

 mens). — Myiarchus tyrannulus tyrannulus (not of Clark, 1905,= If. oheri nugator) Hell- 

 mayr, Novit. Zool., xiii, 1906, 26 (Trinidad; crit.). — Myiarchus tyrannimis (error) 

 Allen, Bull. Am. Mus. N. H., ii, 1889, 87 (Mapiri, Bolivia). — [Pyrocephalus] tyrannulus 

 Gray, Hand-list, i, 1869, 363, no. 5527.— Muscicapa aurora Boddaert, Tabl. PI. Enl., 

 1783, 34 (based on Le petit Tyran de Cayenne Daubenton, PI. Enl. 571, fig. 1). — [Musci- 

 capa ferox] ft Gmelin, Syst. Nat., i, 1788, 934. — Myiarchus cnnitus (not Turdus crinitus 

 Linnseus) Hartlaub, Index Azara Apunt., 1847, 13; D'Orbigny, Voy. Amer. Merid., 

 Ois., 1839, 306. — [Tyrannula] irritabilis (not Tyrannus irritabilis Vieillot, 1823) Bona- 

 parte, Consp. Av., i, 1850, 189, part. — Myiarchus crinitus, b. var. irritabilis Coues, Proc. 

 Ac. Nat. Sci. Phila., 1872, part (Paraguay). — Myiarchus crinitus, var. irritabilis Baird, 

 Brewer, and Ridgway, Hist. N. Am. Birds, ii, 1874, 331. — Tyrannus ferox {i\oi Musci- 

 capa ferox Gmelin) Vieillot, Enc. Meth., 1823, 848. — Myiarchus ferox Bvirmeister, Syst. 

 Ueb. Th. Bras., 1854, 116, part. — Myiarchus erythrocercus Sclater and Salvin, Proc. 

 Zool. Soc. Lond., 1868, 631,- 632 (Bahia, e. Brazil; coll. P. L. Sclater) .—[ Myiarchus 

 erythrocercus] var. erythrocercus Ridgway, Proc. U. S. Nat. Mus., i, 1878, 140, 141, part 

 (crit., etc.). 



b Not having seen a specimen of this form I am unable to give a better comparative, 

 diagnosis. 



