Bangs Birds from Costa Rica and Chiriqui. Ill 



Chlorophanes spiza (Linn.). 



The twenty-six skins of Chlorophanes spiza in the Underwood collection 

 from Pozo Azul and San Jose are intermediate between subspecies guate- 

 muleiMx and exsul though rather nearer the latter. None of them have as 

 long bills as the northern form and none are quite so large, and although 

 none have quite the small size and short bill of exsul, several speci 

 mens might well pass for that form. 



Dacnis cayana callaina Bangs. 



The Underwood collection contains nine skins of this form, three of them 

 fully adult males, all from Pozo Azul, thus extending the range of the 

 Chiriqui form to western Costa Rica. Unfortunately there were no skins 

 from other places in Costa Rica, but I fancy ullramarina is the subspecies 

 that inhabits the eastern part of the country. 



Icterus prosthemeles Strick. 



There is in the southern part of the range of Icterus proslhemeles a ten 

 dency toward a curious phase of plumage that apparently never occurs 

 among birds from Mexico or Guatemala. In a series of southern specimens 

 some can always be found that show much black mottling on flanks and 

 have the black of breast extended far backward over the belly, and in a few 

 specimens the black of the back also encroaches much on the yellow rump 

 patch. If all southern examples were alike, no ornithologist would hesi 

 tate to recognize a southern form by name, but they are not. In fact the 

 larger number of specimens from Panama to Honduras are quite like Mex 

 ican examples. It may be that in time this tendency among southern 

 examples to show much more black than northern ones will become a 

 fixed character, but at present it certainly is not. 



In the Underwood collection there were but two skins of this species, one 

 the blackest I have ever seen, the other exactly like ordinary Mexican 

 specimens. 



Icterus sclateri Cassin. 



In Birds of North and Middle America, part II, pp. 297-298, foot-note, 

 Ridgvvay suggests that perhaps two forms of this striking oriole may really 

 exist, Icterus sclaleri sclateri Cassin, Nicaragua to Costa Rica, and 1. sclaleri 

 fortnosas (Lawr.), Honduras to Oaxaca. 



In the Underwood collection there is a fine pair from Miravalles, Costa 

 Rica. These and my one Mexican example, Nelson compared for me with 

 all the material in Washington, and found no appreciable difference in 

 size between northern and southern specimens. Southern skins have the 

 back more solidly black than northern, but the difference is slight and 

 perhaps partly due to season the southern specimens examined being in 

 freshly acquired autumnal plumage, and there seems no need for a sub 

 division of the species. 



