Fig. 6. Dlx1^-/-;6^-/- and Dlx2^-/-;6^-/- head skeleton phenotypes. Head skeleton and skeletal elements of E18.5-P0 mice stained with Alcian Blue (cartilage) and Alizarin Red (bone). (A-F) Lateral views of the whole head. (G-L) Dentaries. (M-R) Skull base views; the right half is a mirror image of the left half with individual skeletal components highlighted by color. (S-X) Oblique lateral views of the head after removing dentary. (Y-d) Middle ear ossicles, ectotympanic and gonial. Note that os paradoxicum (OP) of Dlx1^-/-;6^-/- and Dlx2^-/-;6^-/- has been integrated into the skull base (see Fig. S6E,F in the supplementary material), and thus excluded from c and d. avp, alveolar process; BS, basisphenoid; E, eye; PT, pterygoid; for remainder, see legends to Figs 4 and 5. ^*, duplicates found in the mutants. Scale bars: 1 mm.