DETAILED LIST OF BIRDS. 
227 
It appeared that in P. maculatus the whole upper surface 
was greener, the tail feathers were edged with greenish, the 
striations of the back were very narrow and but little 
conspicuous ; the supercilium above the posterior angle of 
the eyes continued backwards over the ear-coverts was 
nearly pure white ; the abdominal plumage was whiter. In 
P. arboreus the upper surface was brown, the tail feathers 
were not edged exteriorly with green, but with pale buff; 
the striations of the back were broad and conspicuous, the 
supercilium of less extent and buffy throughout, the abdo- 
minal region more buffy. Accepting these points of dis- 
tinction, all the Yarkand birds, without exception, must be 
referred to P. arboreus. I have said that the two forms are 
easily separable, but it does not, therefore, necessarily follow 
that they belong to distinct species : it is still, it seems to 
me, quite possible that P. maculatus may be the young bird 
of P. arboreus, and although this involves the supposition 
that this bird, contrary to the analogy of all similar species, 
does not assume adult plumage until the second year, there 
are yet two points which favour the suspicion : the first is, 
that some summer-killed P. maculatus are scarcely dis- 
tinguishable from P. arboreus killed at the same season ; the 
second that I have birds sent from England as P. arboreus^ 
and supposed to have been there killed, which, if obtained 
in India, we should certainly class as P. maculatus. Nothing 
is easier than to separate all specimens obtained during the 
cold season in the plains, as belonging to one or the other 
species or race. Some specimens killed early in summer in 
the hills seem more or less intermediate between the two. 
If they really are distinct, then I suspect that P. maculatus 
occurs in England as well as P. arboreus. It would be 
interesting if European Ornithologists would see whether 
they obtain Tree Pipits presenting the distinctive characters 
above pointed out as pertaining to what we call P. maculatus 
here. {A. O. 
604. Agrodroma Jerdoni (Finch). (PL xxi.) 
Corydalla griseorufescens. Hume. Ibis, 1870, p. 286. 
A specimen of this large Pipit, which is equally common 
in the plains during the cold season, and the hills during 
Q 3 
