Figure 16.

Eudyptula minor, CT Vox reconstructions of Larynx and Trachea using micro‐CT (specimen L1), demonstrating both the limit of resolution of skeletal elements and the ability of micro‐CT to retain accurate spatial orientation of these small bones, useful when drawing Figure 10. (a) Dorsal and (b) ventral view of Apparatus hyobranchialis. Ossification of Cartilago cricoidea was only just visible with very fine adjustment of the transfer function in CTVox for bone, because of the small degree of density differentiation from the surrounding tissue, a result of its thinness and depth. In particular, the parasagittal Cartilago cricoidea did not appear completely ossified when reconstructed despite raw data and dissection showing that it was. It was also observed that the first two tracheal rings were open dorsally and did not form a complete ring. They were also fused to each other, except where they articulated with the caudal extension of Cartilago cricoidea. The first five tracheal rings were all open ventrally. The more caudal rings were completely closed, although their ventral portion was thinner than the rest of the ring