^* It is inco:icievable that Lichtenstein v;ould 

 have called these birds mesoleuca in one description 

 and later given the.ii another naT^e with no word of 

 explanation. Furthermore Cabanis and Heine in 

 the list of synonyms of ContoDus cooperi Tie 

 Iluttalornis borealisj in :.:us. Hein. 2, 1859, p. 72, 

 list villicus as a synonym of that species. Certainly 

 they never associated the name mesoleucus vdth the 

 olive sided flycatcher. 



There is a specimen of a South American fly- 

 catcher in the Berlin Museum labelled M. mesoleuca N. 



Montevideo' 2506 Salle 

 It is the only flycatcher in the collection "bearing 

 a label (old or nev;) vdth such a name inscribed. This 

 bird (fide Dr. Stresemann) was in the collection at 

 Berlin at the time I.luscicapa mesoleuca v;as described 

 and is, therefore, without doubt the bird Lichtenstein 

 had in hand at the time. I.loreover it is a gray-green 

 bird vdth whitish throat and belly, thus in accord 

 with the description. It is. probable that this name 

 appeared in the list of Mexican birds through oversight 

 for in the aforementioned Nomenclat or. (1854) 

 Lichtenstein lists tv.-o specimens of " Myiarchus " villicus " 

 frqm Mexico and one specimen of "Elaenea mesoleuca" 

 from Montevideo* . 



'^* Cabanis and Heme, five years after Lichtenstein 



Nomenclatar appeared described (Mus. Hein, 2, 1859, 

 p. 60) the identical species under .the name of Elaenia 

 mesoleuca / i)asing their description on a specimen in 

 the Museum Heineanum from Rio Grande [do Sul, south 

 eastern Brazil]. 'vVhether they used this name through 

 coincidence or not is imira-terial. The fact remains 

 that Lichtenstein 's type -o f Muscicapa mesoleuca is 



extant and his description, brief as it is, is perfectly 

 applicable to the type, . •. 



A- The citation for Elaenea mesoleucus should, 

 therefore, be corrected to read Elaenea mesoleucus 

 (Lichtenstein). 



Muscicapa m.esoleuca Lichtenstein, Preiz. Verz. 

 Mex. V5g, , 1830, p. 2 ("Mexico" [errore = Montevideo, 

 Uruguay]. ^^ j, y^n Rossem 



