Abstract
Cashmere down and superfine merino wool fibers obtained from a number of sources were examined by transmission electron microscopy. All fibers, regardless of crimp, showed a bilateral cortical structure. Most cashmere and superfine merino fibers could be distinguished from each other by the nature of their cortical cells. The cortex of cashmere contains predominantly orthocortical and mesocortical cells. The cortex of superfine merino, on the other hand, contains predominantly orthocortical and para- cortical cells. The proportion of orthocortical cells found in the cross sections of su perfine merino wool was slightly higher than for cashmere.