FAMILY FORMICARIIDAE 20$ 



but in figures 2 and 3 from specimens of Myrmeciza immaculata that 

 apparently were not fully adult. 



MYRMECIZA EXSUL NIGLARUS Wetmore 



Myrmecisa cxsul niglariis Wetmore, Smithsonian Misc. Coll., vol. 145, no. 1, 

 June 26, 1962, p. 7. (Rio Chiman, about 10 kilometers above Chiman, Province 

 of Panama, Panama.) 



Characters. — Male, crown and hindneck black, like exsul, but rest 

 of dorsal surface lighter brown, in shade between exsul and occi- 

 dentalis; below definitely paler than exsul ; very faintly darker than 

 occidentalis. 



Female, generally similar to that of exsul, but averaging lighter 

 and brighter on lower surface posterior to the foreneck ; breast 

 brighter brown ; definitely darker than occidentalis. 



A male, taken March 1, 1961, on the Ouebrada Candelaria, Panama, 

 had the iris dark brown ; bare skin on side of head from lores to 

 above the auditory region clear blue ; bill black ; tarsus and toes 

 fuscous-black. 



In a female from Canita, Panama, February 6, 1962, the iris was 

 dull reddish brown ; bare skin on side of head light blue ; bill black ; 

 tarsus, toes, and claws dark neutral gray. 



Measurements. — Males (15 from eastern Province of Panama and 

 San Bias), wing 65.0-70.1 (67.1), tail 42.5-49.7 (45.7), culmen from 

 base 20.2-22.3 (21.4), tarsus 27.5-29.7 (28.4) mm. 



Females (10 from eastern Province of Panama and San Bias), 

 wing 62.7-67.0 (64.2), tail 40.2-47.6 (43.3), culmen from base 

 19.9-22.2 (20.8), tarsus 26.4-29.6 (28.1) mm. 



Resident. Eastern Panama ; Pacific slope from western end of 

 Cerro Azul east through the Province of Panama to eastern Darien; 

 on the Caribbean slope from the upper Chagres Valley, above Madden 

 Lake (Quebrada Candelaria on the Rio Pequeni, Quebrada Peluca 

 on the Rio Boqueron) east through San Bias to the Colombian 

 boundary. 



Specimens from Acandi on the coast of extreme northern Choco 

 in Colombia, about 20 kilometers beyond the boundary with Panama, 

 also belong to this race. This point marks its most eastern and 

 southern extension, as immediately beyond, the next race M. e. 

 cassini appears. Since niglarus is the race found at Chepo it is sup- 

 posed that this form ranges up the valley of the Rio Bayano, though 

 there are as yet no specimens from that area. 



