Carriker : List of the Birds of Costa Rica. 909 



although the wing formula is that of A. b. petenica (Salvin), at present 

 known only from the type. Measurements are as follows: wing, 61 ; 

 tail, 60; exposed culmen, 13; tarsus, 19.5 mm. In the absence of addi- 

 tional specimens, and in view of the uncertainty of the status of this latter 

 form, it is perhaps best to refer our specimen, at least provisionally, to 

 sartoriir (W. E. C. Todd.) 



To Mr. C. H. Lankester belongs the credit of first adding this species 

 to the Costa Rican ornis, he having taken the first specimen at Miravalles 

 in May, 1906. The birds were secured on the grassy slopes about 

 Miravalles, in the same localities as Aimophila rufescens hypccthrus. 



746. Aimophila rufescens hypaethrus Bangs. 



Hcemophila rufescens (not Pipilo rufescens Swainson) Underwood, Ibis, 1896, 



436 (Miravalles, Costa Rica). 

 Aimophila rufescens rdfescens Ridgway, Birds N. and Mid. Amer., I, 1901, 



Addenda, p. 673 (Costa Rica; authority record of Underwood, cited above). 

 Aimophila rufescens hypcethrus Bangs, Proc. Biol. Soc. Wash., XXII, 1909, 37 



(type from Cerro de Santa Maria, Costa Rica, cf, January 4, 1908, C. F. 



Underwood; coll. E. A. and O. Bangs). 



Bangs Collection: Cerro de Santa Maria and Tenorio (Underwood). 



Eight skins. 

 C. H. Lankester Collection: Miravalles. 

 Carnegie Museum: Miravalles (Carriker). Six skins. 



This appears to be a well marked southern race of Aimophila rufescens, 

 resembling true rufescens of northern Mexico, except that it is smaller, 

 with the bill actually larger. It is not at all strange that this isolated 

 colony of birds in northwestern Costa Rica should be distinct, when the 

 wide gap separating them from their northern allies is considered. It 

 was first reported by Underwood in 1896, from Miravalles, at which time 

 he took several specimens which were identified by Salvin as Hcemophila 

 rufescens. The bird was not taken again until 1906, when Mr. Lankester 

 and myself took a small series, also at Miravalles. The next year Under- 

 wood again took specimens which Mr. Bangs discovered were different 

 from any described form, and gave it the name used above. 



Its range is confined to northwestern Costa Rica, north of the head of 

 the Gulf of Nicoya, and on the Pacific foothills. It probably extends up 

 into Nicaragua, although it has not been reported from that country < 

 The birds are found in open country, where there are scattering bushes 

 and scrubby trees. 



