Barb fragment from 350°C feather.

Abstract

<p>(A) Barb ramus retaining barbule protrusions (arrows) allows definitive identification as a barb fragment. Only the most proximal parts of the barbules can be observed where they branch from the ramus. (B) Transmitted light image of a 200nm thin section of a barb from the 350°C treated feather (similar to A) shows presence of external cortex (arrowhead) and inner pith observed as honey-comb texture.</p