Abstract
A bstract X‐rays of mandibles from ringed seal fetuses ( n = 15), newborns ( n = 12), and young‐of‐the‐year ( n = 11), collected up to early June, were examined for the presence, location, and eruption patterns of deciduous and permanent teeth. The presence of a neonatal line and cementum in permanent canines was determined microscopically. Fetuses sampled in October‐November had only unerupted, deciduous tooth germs, but by late January there were robust, deciduous teeth at il‐2 pc2‐4 and small permanent teeth at 11‐2 Cl PCl‐5. In newborns collected in early April, 109 of 143 (76%) deciduous teeth were resorbed completely. The remaining 34 deciduous teeth were partially resorbed; six (18%) had erupted and likely would be shed. By late April young‐of‐the‐year had no deciduous teeth remaining. In newborns 54% of the permanent teeth (102/188) were erupted