EMPIDONAX. 73 



discriminate every individual. A hundred and odd specimens before us conform fairly 

 to the characters of this bird as given above, but we notice slight differences in 

 coloration vphich we believe to be due to differences of season : thus birds shot in 

 Central America in early spring agree fairly well with North-American examples killed 

 during the breeding-season, but autumn birds have greyer throats and more distinctly 

 yellow bellies. The slightly forked tail of ^. minimus seems to be the best character by 

 which to distinguish it from E. trailli, and in naming our series from Mexico and Central 

 America we have been governed by it rather than by measurement and slight modifica- 

 tions of colour. The difference in the colour of the eggs of E. minimm, which are 

 spotless buffy white, and those of E. trailli, which are spotted with deep rusty brown, 

 at once shows that the two birds are really quite distinct. 



E. minimus enjoys a wide range throughout Eastern Mexico and Central America in 

 the winter months, but it appears to be absent from Western Mexico and the central 

 plateau, and only crosses to the Pacific coast at the Isthmus of Tehuantepec. In 

 Guatemala it occurs on both sides of the cordillera and in the mountains up to an 

 elevation of 5000 or 6000 feet. At higher altitudes in the Volcan de Faego its place 

 is taken by E. hammondi. 



d. Suhtus flavus. 

 6. Empidonax flaviventris. 



Tyrannula flaviventris, W. M. & S. F. Baird, Pr. Ac. Phil. 1843, p. 283 \ 



Empidonax flaviventris, Baird, B. N. Am. p. 198 ' ; Scl. P. Z. S. 1859, p. 366 ' ; Cat. Birds Brit. Mus. 



xiv. p. 230* J Scl. & Salv. Ibis, 1859, p. 122" j P. Z. S. 18G4, p. 360 ^ 1870, p. 837"; Lawr. 



Ann. Lye. N. Y. viii. p. 8', ix. p. 114'; Bull. U. S. Nat. Mus. no. 4, p. 27"; Sumichrast, 



Mem. Bost. Soc. N. H. 1. p. 557"; Baird, Brew., & Ridgw. N. Am. B. ii. p. 378"; Salv. 



P. Z. S. 1870, p. 199"; Coues, Birds N. W. p. 255"; Key N. Am. B. ed. 2, p. 442"; 



Nutting & Ridgw. Pr. U. S. Nat. Mus. vi. p. 384"; Ridgw. Ibis, 1886, p. 466"; Man. N. 



Am. B. p. 341 ". 

 Tyrannula ?, Scl. P. Z. S. 1856, p. 296, no. 107". 



Supra olivaceus ; capite summo vix obscuriore ; alia nigricantibus, teetricibus flavo-albido late terminatis fasciis 

 duabus formantibus, seoundariis iaternis late reliquis anguste extrorsum flavo-albido limbatis; oculorum 

 ambitu pallide flavido : subtus flavus ; pectore et hypoohondriis olivaceo limbatis ; subalaribus flavidis : 

 rostri maxilla nigricante, mandibula flava ; pedibus nigricantibus. Long, tota 4"5, alae 2-6, caudse 2-0, 

 tarsi 0'7, rostri a rictu 0"6. (Descr. maris ex Jalapa, Mexico. Mus. nostr.) 



Hob. Eastern North America. — Mexico, Sierra Madre above Ciudad Victoria and 

 Xicotencal in Tamaulipas ( W. B. Richardson), State of Vera Cruz {Sumichrast ^^), 

 Colipa {F. B. G.), Jalapa {de Oca^, M. Trujillo), Cordova {Salle ^% Teapa in 

 Tabasco {Mrs. H. H. Smith), Guichicovi, Sta. Efigenia {Sumichrast ^^) ; Guatemala 

 {Skinner % Choctum, Coban, Duenas, Eetalhuleu {0. S. & F. B. G.) ; Honduras, 

 San Pedro {G. M. Whitely '') ; Nicaragua, Sucuya {Nutting i^) ; Costa Eica, Ango- 

 BiOL. cente.-amer., Aves, Vol. II., February 1889. 10 



