"Parts of a feather. I., Four barbs (B.) bearing anterior barbules (A.BB.) and posterior barbules (P.BB.); II., six barbs (B.) in section, showing interlocking of barbules; III., anterior barbule with barbicels (H.)." -Thomson, 1916

Feather Parts

"Parts of a feather. I., Four barbs (B.) bearing anterior barbules (A.BB.) and posterior barbules (P.BB.);…

"Types of feathers. D., Down. 2, Developing feather in sheath (sh.). 3, Covert of heron showing aftershaft (A.S.). 4, Secondary feather of pigeon--C., calamus; A.S., aftershaft; R., rachis; V., vane. 5, Portion of quill showing inferior umbilicus (I.u.), superior umbilicus (S.u.), pith (P.); F., filoplume." -Thomson, 1916

Feather Types

"Types of feathers. D., Down. 2, Developing feather in sheath (sh.). 3, Covert of heron showing aftershaft…

"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.…