1917.] Chapman, Distribution of Bird-life in Colombia. 373 



their allottment to genera of certain Formicarian birds, pending a thorough 

 revision of the groups concerned, based on adequate material of the known 

 species. The present species, for example, is obviously not referable to 

 Dysithamnus, but in most cases the purposes of this paper, are, in my opinion, 

 best served by using the nomenclature of a standard Check-List rather 

 than by the expression of individual opinion based on only a partial survey 

 of the field. 



La Morelia, 2; Florencia, 1. 



(1953) Dysithamnus ardesiacus ardesiacus Scl. 

 Dysithamnus ardesiacus Scl. & Salv., P. Z. S., 1867, p. 756 (Rio Napo). 



Found in the Tropical Zone of Amazonian Colombia. Our specimens 

 differ from lower Orinoco and British Guiana specimens of D. a. saturinus 

 in the smaller amount of black on the throat of the male. 



La Morelia, 4; Florencia, 3. 



(1959) Thamnomanes glaucus Cab. 



Thamnortianes glaucus Cab., Arch. ftir. Naturg. 1847, p. 230 (Cayenne). 



Found in the Tropical Zone of Amazonian Colombia. Four males are 

 slightly darker than recently collected specimens from British Guiana. 

 La Morelia, 5; Florencia, 1. 



(1961) Myrmotherula pygmaea (Gmel.). 



Muscicapa pygm(Ba Gmel., Syst. Nat. I, 1789, p. 933 (Cayenne). 



Myrmotherula pygmma Cass., Proc. Acad. N. S. Phila., 1860, p. 190 (R. Truando) . 



We have specimens of this wide-ranging species from the Tropical Zone 

 of the Pacific coast and from Amazonian Colombia. They agree with others 

 fronj British Guiana. 



San Jose, 1; Florencia, 1; La Morelia, 1. 



(1963) Myrmotherula surinamensis pacifica Hellm. 



Myrmotherula surinamensis pacifica Hellm., P. Z. S., 1911, p. 1159 (Type from 

 Buenaventura; also specimens from Rio Calima; Sipi; near Naranjo, 2800 ft.). 



Myrmotherula surinamensis Cass., Proc. Acad. N. S. Phila., 1860, p. 190 (Turbo); 

 Scl. & Salv., P. Z. S., 1879, p. 525 (Remedios). 



Inhabits the Tropical Zone of the Pacific coast and eastward to the 

 Magdalena. Comparison of our specimens from this region with a recently 



