The Siberian Chiffchaff — Phylloscopus Tristis, Blyth
One example of this small warbler, that breeds in Western Siberia, migrating to Turkestan and India in winter, was obtained at a lighthouse off the Orkneys in 1902. It is rather smaller and browner than our common Chiffchaff and has the under parts buffish white. It may, however, always be recognised by the shortness of the second primary, which comes between the seventh and the eighth, or is even shorter than the eighth.