Mountain chiffchaff Caucasus, but interbreeding occurs rarely, if ever. The mountain chiffchaff differs from "tristis" in vocalisations, external morphology and mtDNA sequences. Its two subspecies appear to be distinct vocally, and also show some difference in mtDNA sequences. Mountain chiffchaff The mountain chiffchaff or eastern chiffchaff ("Phylloscopus sindianus") is a species of leaf warbler found in the Caucasus ("P. s. lorenzii") and Himalayas ("P. s. sindianus"), and is an altitudinal migrant, moving to lower levels in winter. The nominate subspecies is similar to the Siberian chiffchaff, but with a finer darker bill, browner upperparts and buff flanks; its song is almost identical
Handbook to the Birds of Australia says in his Preface: ”Nearly twenty years have elapsed since my folio work on the Birds of Australia was completed. During that period many new species have been discovered, and much additional information acquired respecting those comprised therein; consequently it appeared to me that a careful "résumé" of the entire subject would be acceptable to the possessors of the former edition, as well as to the many persons in Australia who are now turning their attention to the ornithology of the country in which they are resident. Indeed I have been assured that such a work is greatly needed to