192 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 



depth of bill at l):i80, L2.2-ir).2 {18); tarsus, 30.2-34:.8 (31.5); middle 

 toe, 19.8-24.1 (i>l.(;).' 



Western Mexico, north to State of Sinaloa (Mazatlan, Rosario, etc.), 

 south through territory of Tepic and States of Jalisco, Colima, Guer- 

 rero, andOaxaca (Barrio, Chihuitan, Tehuantepec City, etc.) to Chiapas 

 (Tonala). 



Icleriix tiidaiiicteruf! Bonaparte, Jdui'ii. Ac. Nat. Sci. Phila., iv, 1825, 3S9 (Mex- 

 ico). 



Clncims'} melanictcrun (tKAY, Gen. Birds, ii, 1849, 342. 



[Castiiculus'] mehmicterus Bonaparte, Consp. Av., i, 1850, 428. — Sclatek and Sal- 

 viN, Noni. Av. Neotr., 1878, 35. 



C [rt.s.sic?/iu.S'] melanictems C\B\'si», Mus. Hein., i, 1851, 186. 



CnK><iri(lns vu'lanicterns^CLXTER, Proc. Zool. Soc. Lond., 1859, 380 (Rio (Trande, 

 Oaxaca); Cat. Am. Birds, 1862, 129 (Oaxaca); Ibis, 1883, 156 (nionogr.); 

 Cat. Birds Brit. Mus., xi, 1886, 328 (Tonala, Chiapas; Acapidco, (Jnerrero; 

 Presidio and Mazatlan, Sinaloa). — Dcges, La Naturaleza, i, 1869, L39 (Guer- 

 rero, Mexico). — FiNscH, Abb. Nat. Ver. Brem., 1870, 263 (Mazatlan). — 

 Lawrence, Mem. Bost. Soc. N. H., ii, 1874, 278 (Mazatlan; Tepic; Colima; 

 Rio de Coahuyana; habits; descr. n(>st and eggs). — Lawrence, Bull. U. S. 

 Nat. Mus., no. 4, 1876, 23 (Barrio, Chihuitan, and Tehuantepec City, Oax- 

 aca). — Salvin and (tooman, Biol. Centr.-Am., Aves, i, 1883, 443. — Fkkrari- 

 Perez, Proc. U. S. Nat. Mus., ix, 1886, 149 ( Yanhuitlan?, Oaxaca). 



Cassicm vuiamrterm Cassin, Proc. Ac. Nat. Sci. Phila., 1S67, 66 (nionogr. ; Mazat- 

 lan; Acapulco). 



Ps{cirocolms\viel(tnict(:ruii'\\ XGi^EK, Isis, 1829, 752 (Mexico). 



Icterus diadematus Temminck, PL Col., 1829, pi. 482 and text (Mexico;=female). 



Casslculus coronatus Swainson, Philos. Mag, new ser., i, 1827, 436 (Temascal tepee, 

 Mexico); Zool. Journ., iii, 1827, 353. 



Xantliormis roronatni^ Jardine and Selhy, Illustr. Orn., 1828, j)l. 45 (Mexico). 



Genus AMBLYCERCUS Cabanis. 



AmhlijccrcuH''' Cabanis, Mus. Hein., i, Sept., 1851, 190. (Type, Cassicus nir/er- 

 rbnna Spix, = C mlitarivK Yieillot.) 



Medium-sized or rather small uniformly black Icteridie with short 

 and excessively rounded Avino" (outermost primary shorter than inner- 

 most) and ti[) of the wedge-shaped, light-colored bill broad and con- 

 spicuously flattened. 



Bill al)out as long as head or a little shorter, cimeate-conical, com- 

 pressed, with tip broad and truncate in vertical but acute in lateral 

 profile, its basal depth a little less than half the culmen, its basal width 

 a little less than half the distance from nostril to tip of maxilla; cul- 

 men straight, broad, and flattened, with parallel edges of flattened 

 surface not ridged, the ])ase not elevated; commissure straight to 

 beneath nostril, where gradually deflexed to the rictus. Nostril ])elow 

 lateral median line of maxilla, small, narrowly oval or slit-like, 



^ Five specimens. 



^ " ajit/JAvs, stumith, u. KepKu^, Schwanz." 



