Red-tailed Bush-Lark. 471. 
In my specimen e the pale edges of the wing-coverts have 
practically disappeared ; in a they remain only on the greater 
coverts; in 6, c, and d they have suffered less from wear. 
In all the five specimens the first five or six primaries shew 
no pale ends, the remaining primaries and outer secondaries 
are in perfect condition, with broad rufous-white ends. Ine 
and d the dark markings on the crop are more distinctly in 
the form of spots than in the other examples, in which the 
markings are heavier and run more together. On the chest 
they assume a sharply-defined lanceolate form, and in a 
and e these pointed markings extend down the whole centre 
of the breast; in 6 and ¢ there are only a few on the breast, 
d the breast is almost uniform buff, with a strong rufous 
and in suffusion. The under tail-coverts vary from rufous 
buff to pure cinnamon. 
In the dorsal plumage of specimen 6 I find four or five 
concealed new feathers, not fully developed, of an ashy 
black, with broad and distinct rufous margins. Abrasion in 
this species appears to occur very rapidly, but I do not doubt 
that the new and perfect dorsal plumage is ashy black, 
mottled all over with scale-like edgings of bright rufous. ‘This, 
indeed, is how the adult male of Mirafra nigricans (in winter 
plumage) is described by Stark, though this plumage would 
appear to be assumed by M. erythropygia in the summer. 
(It is, by-the-way, a great pity that the dates at which 
the specimens described, and the specimens recorded from 
different localities were obtained, are so often omitted in the 
Bird-volumes of the ‘ Fauna of South Africa.’) 
I fear that I have occupied a great deal of space over this 
one species, but I think that wrong conclusions have been 
drawn from the limited number of specimens hitherto avail- 
able for examination, and that this has led to an unsound 
diagnosis of an unnecessary genus. 
In concluding, I would add that the loss of pale margins 
to the feathers of birds by “ abrasion,” so complete in M. ery- 
thropygia, seems to me to be due to the fibre of the feathers 
being weaker and more perishable in white or slightly pig- 
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