ClipArt ETC
"A., Filoplume. B., very young feather within its sheath (sh.); c., the core of dermis; b., the barbs. C., the same, external view." -Thomson, 1916

Feathers

"A., Filoplume. B., very young feather within its sheath (sh.); c., the core of dermis; b., the barbs.…