calamus

bird anatomy

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Last updated

July 16, 2026

Quick Summary

feather types Feather types and their distribution on a typical perching bird.

The calamus is the hollow, basal portion of a feather that lies beneath the skin. It is part of the central shaft, or rachis, from which the feather's barbs branch out. This structure is essential for feather growth and anchoring it to the bird's skin. The term "calamus" can also refer to the sweet flag plant or its rhizome.12

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Feathers
…the rachis is called the calamus, part of which lies beneath the skin. The barbs, in turn, have branches, the barbules. The barbules on the distal side of each barb have hooks (hamuli) that engage the barbules of the next barb. The barbs at the base of the vane are…
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…the rachis is called the calamus, part of which lies beneath the skin. The barbs, in turn, have branches, the barbules. The barbules on the distal side of each barb have hooks (hamuli) that engage the barbules of the next barb. The barbs at the base of the vane are…
Read More