NO. 191C. REVISION OF DUTORIDES TIRESCENS—OBERnOLSER. 



551 



both probably unusually large examples of Butorides virescens hyper- 

 notius; at least, it seems best to consider them such, rather than as 

 migrant individunls of Butorides virescens virescens. 



The specimens from Costa Kica, Colombia, and Venezuela exam- 

 ined are, in both size and color, aj)parently just like those from 

 Panama. Average measurements of birds from these regions are as 

 follows : 



Localities. 



Five malos, from Panama 



Three males, from Colombia and Venezuela 



Six males, from Costa Rica 



Five females, from Panama .-. . . 



One female, from Costa Rica 



Middle 

 toe. 



mm. 

 44.9 

 45.2 



45.3 

 43.9 

 43.0 



This form is apparently resident throughout most, if not all, of its 

 range, although, heron-like, it probably wanders more or less before 

 and after the breeding season. It is possible, however, that in the 

 southernmost part of its distribution it is migratory, for there are 

 records of its occurrence in southern South America; yet these need 

 confirmation. 



I have seen 28 examples, from the localities below, breeding rec- 

 ords having an asterisk: 



Colombia. — Honda (Tolima); Mamatoca; Bonda (Santa Marta). 



Costa Rica. — Vicinity of San Jose; Talamanca; Pozo del Rio 

 (Irande (Boruca) ; Bolson; Lipurio; Azahar de Cartago. 



Panama. — Rio Indio, near Gatun (Canal Zone); Gatun; Frijoles; 

 Rio Caiio Quebrado (near Tabcrnilla) ; Sona.* 



Venezuela. — Chama (near Merida); Rio Muenpen (near Merida). 



