. A history of birds . M l-,M »ll \ FKAFHKK ()F TAWXN (i\\|.. MESOPTVLE FEATHKR OF THE BARN-OWL THE LIFE-HISTORY OF BIRDS 271 The Passerine birds present us with the other extreme ofnesthng- pkimage, in that the down feathers are here but feeblydeveloped, or are absolutely wanting, as in the Sparrow andCrow tribe. Young Larks and Wagtails have more down thanThrushes, but this is never developed save in certain restrictedareas. That is to say, instead of every contour feather beingpreceded by a down feather, as in the young of nidifugousbirds, only a few have these fore-runners. Thus a row
. A history of birds . M l-,M »ll \ FKAFHKK ()F TAWXN (i\\|.. MESOPTVLE FEATHKR OF THE BARN-OWL THE LIFE-HISTORY OF BIRDS 271 The Passerine birds present us with the other extreme ofnesthng- pkimage, in that the down feathers are here but feeblydeveloped, or are absolutely wanting, as in the Sparrow andCrow tribe. Young Larks and Wagtails have more down thanThrushes, but this is never developed save in certain restrictedareas. That is to say, instead of every contour feather beingpreceded by a down feather, as in the young of nidifugousbirds, only a few have these fore-runners. Thus a row ofdown feathers occurs over each eye and a few around the back ofthe head, while a row of downy tufts runs down the scapulartract, and a similar row along the spinal and femoral the under-surface is always bare. That this condition hasbeen derived from a more complete covering is shown by thefact that the Lyre-birds alone among the Passeres have a com-plete downy covering, and these birds represent, probably, themost primitive members of the group. T
Size: 1857px × 1345px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjectbirds, bookyear1910
