Orbitosphenoid, squamosum and alisphenoid in postnatal days 7–15 of Crocidura russula. A In section d7 37-1-2 the ‘Zuwachsknochen’ of the orbitosphenoid begins to contact the squamosum. B In section d7 39-3-1 the orbitosphenoid underlies the squamosum only rostral to the glenoidal region, i.e. the mechanical support for the joint is only indirect. C In section d8 78-2-2 the support of the squamosum is provided by the anterior process of the alisphenoid only. D In section d15 69-2-1 the pars glenoidea of the squamosum is connected with the nasal capsule (ethmoid) by the orbitosphenoid and the alisphenoid. Abbreviations: see Fig. 9, nV2 – nervus maxillaris, pal – palatinum, pco – processus coronoideus, pgi – processus glenoideus inferior.