YELLOW-RUMPED BULL-FINCH. 207 
otter. Geographic distribution and a knowledge of 
otter species then comes to our aid, and in most 
cases enables us to decide, with tolerable accuracy, 
the affinities of such intermediate forms. Of this 
character is the present bird : it certainly belongs 
to the genus Critliagra , which seems the first of the 
Bull-finches, after leaving the linnets. This genus 
is abundant in Africa, where on the other hand the 
linnets, so far as we know, are not to be found. 
Upon the juxta-position of these two genera do we 
account for their very great resemblance. 
Size of the red-pole linnet, upper plumage, in- 
cluding the crown, ears, wings, and tail — olive-grey, 
with a dark stripe down each feather ; a broad stripe 
of bright yellow is above each eye, which meet on 
the front ; and there is another below the ear-fea- 
thers, which leaves a maxillary dark stripe bordering 
on the chin ; the upper tail-covers, and the whole 
of the under plumage, from the chin to the vent, is 
of the same clear and full yellow. The wings and 
the tail are darker than the back ; the lesser and 
greater covers have each an obsolete band of yellow 
at their tips ; while the tail, which is divaricated, 
is distinctly tipt with white. Bill and legs pale. 
In structure, the first quill is hardly shorter than 
the second and third, which are the longest ; the 
tarsus is not longer than the hind-toe ; the claws 
slender, and the bill very little swelled. 
Total length, 4-^ ; bill, T 4 „ ; wings, 2 T 6 0 ; tail 
beyond, t ; from the base, 2 ; tarsus, J. 
