SILVERBILL 157 
SILVERBILL 
Lichenops perspicillatus 
Black ; primaries white with black tips and bases; fleshy ring 
round eye and bill palest yellow; length 5.6 inches. Female: 
above dark brown with light edging to feathers; remiges chestnut, 
with dark brown tips; wing-coverts dark brown with fulvous tips ; 
beneath fulvous white, breast with dark striations ; bill yellowish. 
NATURALISTS have said a great deal about the well- 
known Silverbill (the most important member of 
my “‘ Spectacular’ group), the question as to 
whether the black and red birds are sexes or two 
distinct species having long remained unsettled. 
Azara, writing in the last century, under the heading 
Pico de Plata, rightly described the red bird as the 
female of the black; but unfortunately, in another 
part of his work he described the female again as a 
different species, naming it Suiriri chorreado. Darwin 
also separated the sexes, and gave the name of 
Lichenops erythropterus to the red-plumaged bird. 
He made a minute examination of both, and proved 
to his own satisfaction that it was impossible to 
believe that two birds with so many structural 
differences could be one species. 
When one considers the habits of the two birds, 
even where they are most abundant and seen continu- 
ally, it is indeed difficult to believe that they are one 
and the same species. They are never seen associating 
together, even in the love season, and when I have 
watched a pair actually engaged in constructing their 
nest, they appeared to keep as far apart as possible. 
