Poecilomeres 
“On the other hand, among many species the 
differentiation of colour on the pcecilomeres is 
not so conspicuous as to attract the eye or to 
serve in any way for protection or mimicry, ye¢ 
we still find them marked by differences of colour 
so slight that, unless especially looked for, they 
would never be noticed. 
‘Or, again, some species occasionally, but not 
invariably, show a few white feathers on certain 
parts of their body, and, when such is the case, 
it will be found that these white feathers appear 
on the poecilomeres. . . . There is hardly a 
species in which examples of these poecilomeres 
may not be found. . . . The Kingfisher (4 “edo 
zispida) shows the various head peecilomeres very 
clearly, and as examples of inconspicuous differ- 
ences on these tracts, the rump of the hen sparrow 
(Passer domesticus) and hen chaffinch (Frengzlla 
celebs), the malar stripe and dark ear-patch of 
the hen Yellow Bunting (Embertza cetrznella), 
and the dark ante-orbital patch of the Barn Owl 
(Strix flammea) are familiar examples. And, 
lastly, as an instance of the class where a few 
white feathers frequently, but not invariably, 
appear, the young of the cuckoo (Cuculus cano- 
rus) forms a good example. 
“ These spots may, however, appear in a tran- 
sitory manner, as, for instance, where a change 
of plumage (not necessarily moult) is occcurring.” 
As an instance of this, Bonhote cites the case 
T 289 
