38 Bangs — Rare or Not Well Known Costa Rican Birds. 



back and scajjulars much broader and more conspicuous. From A. 

 rufescens discolor Ridg. of the coastal regions of Honduras and British 

 Honduras the new form differs mucli, being larger, nuich darker above, 

 and much less grayish on sides of head, breast and flanks. 



MEASUREMENTS. 



Remarks — Late explorations have shown that this russet-tailed ground 

 sparrow is a not i;ncommon resident of the mountains of northern Costa 

 Rica, and on his last trip Underwood took specimens on Tenorio and 

 in the Cerro Sta. Maria. On comparing these with the two forms which 

 are geograpliieally nearest I found the Costa Rican bird to be very dif- 

 ferent from either. Nelson, to whom I showed the specimens, also agrees 

 as to its distinctness, and it remains but to give it a name. 



Amaurospiza concolor Cabanis. 



Three specimens from Tenorio, an adult male killed January 26, and a 

 pair, adult male and female, January 25, l'J08. The female is uniform 

 tawny-brown above and on sides, and slightly paler and more cinnamone- 

 ous on throat and middle of belly. So far as I know this is the first 

 female of the species that has been taken. 



Sporophila minuta minuta (Linn.). 



Carriker lately recorded a single immature male taken bj' himself at 

 Buenos Aires, the first Costa Rican example of the species. AVlien Under- 

 wood visited Buenos Aires in May, 1908, he found Sporophila minuta 

 abundant, but wholly confined to the open savanna and exceedingly shy. 

 He coll(H't<:id a series of twenty specimens wliich includes adults of both 

 sexes and immature males. 



