LETTERS TO THE EDITOR. 229 
DRYMOIPUS TERRICCLOR and DryMoIPUS LONGICAUDATUS. 
SiR 
” In reference to Messrs. Butler’s and Hume’s remarks, 
Stray FeatHers, 1875, p. 483, I wish to make one or two further 
observations. 
1. The bill, as in Drymoipus rufescens, is very variable as 
regards size, and I certainly do not find in my series that one 
has a larger bill than the other. In the cold weather the bulk 
of the examples procured will be young birds of the year, and 
short bills will predominate. They are then all in the rufous 
longicaudatus plumage. 
2. The procuring of aJuly example in longicaudatus plumage 
is not conclusive. The bird may have missed the usual spring 
change, or perhaps the autumnal young birds don’t put on the 
summer ¢erricolor plumage the first spring. We know that 
lanthia rujilata and Siphia leucomelanura, also Erythrosterna 
parva do not put on full male plumage during their first spring. 
I have shot males of the two former breeding in the female 
plumage. Perhaps then the young birds of Drymotpus terricolor, 
which must moult later than the parent birds, do not moult again 
in the spring; and thus in a northern part of the country, where 
plumage fades less than in the damp hot southern portions, we 
might have a fairly preserved specimen in typical longicaudatus 
plumage. This question can be worked out by some one who 
has the time and the opportunity. 
3. The two forms have very different tails. This is a strong 
point, but is in favour of identity. I have seen many chang- 
ing birds, and have seen the feathers of the new terricolor tail 
growing alongside of the rufous, and very much longer longi- 
caudatus tail. The new secondaries and tertials, when either 
change is taking place, contract strongly with the old plumage 
of the other form. This is best observed at the autumn 
change, when the new feathers are edged with deep rufous. 
As far as my observation goes, the question of identity is 
established, and we have facts to deal with which cannot be 
disposed of. 
I do not know whether it has been observed that Prinia 
Stewarti undergoes a similar change; acquiring a shorter spring 
tail, and a darker grey head, losing also the faint supercilium 
observable in some autumnal birds; which supercilium, I be- 
lieve, is always present in the young bird. 
CURRUCA AFFINIS AND CURRUCA GARRULA. 
I have examined a great number of the former since I last 
wrote on the subject. The strong point of difference is the 
different form of the two wings: the 2nd quill being propor- 
tionally longer in the HKuropean bird. Its plumage is softer 
