The enlargement of the frontal sinus has been analysed in a longitudinal study of 49 males and 47 females for whom a first lateral cephalogram was available at from 2 to 5 years of age for 88 subjects and from 6 to 11 years for 8 subjects. Thereafter the cephalograms were taken at approximately yearly intervals and in 28 subjects a last cephalogram was taken at 24 years or older. In only six subjects was enlargement of the sinus still proceeding at the time of the last cephalogram . The enlargement was assessed by a standardized measurement of the maximum vertical height of the sinus. The median age for the first appearance of the frontal sinus was 3 X 25 years for the boys and 4 X 58 years for the girls. It enlarged on average to 32 X 60 mm (SD 9 X 10) in the males and 26 X 60 mm (SD 7 X 50) in the females. The median age at which the main increase in size of the sinus ceased was 15 X 68 years for boys and 13 X 72 years for girls, thus suggesting that the enlargement of the frontal sinus, a mainly osteoclastic activity, follows very closely the trends for growth in bone lengths.

Skulls of red deer (Cervus elaphus of known age were examined. A scoring procedure devised for fallow deer (Dama dama) was used to relate tooth wear to a particular age (Brown & Chapman, 1990). The precise sequential nature of tooth wear as it appeared on the slopes and tips of cusps, on the marginal ridges and links between cusps was recorded. From these data a base has been provided from which estimates of age may be made of animals of unknown age. The variability for the scores are given for 95% prediction intervals from the regression of age on total molar wear score.

The stages of permanent tooth development observed in radiographs of the mandible are described and analysed for known‐aged red deer (Cervus elaphus). The ages by which the different stages of development were reached have been determined. By allocating scores for these different stages, the scores that may be expected for a particular age have been identified. Lastly, the predicted age was given, together with 95% prediction intervals obtained from a regression of age on total molariform scores. Tooth development in red deer was usually completed by 33 months. These data can be used to assess the ages of animals of unknown age.

The sequence of tooth wear was determined from skulls of fallow deer of known age. A system for scoring molariform tooth wear has been devised so that small but readily recognizable wear changes of the individual cusps may be recorded and used to assess the age of animals of unknown birth dates. The technique can be readily adapted for other ruminant species with the appropriate database.

The stages of permanent tooth development observed in radiographs of the mandible were described for known‐aged fallow deer Dama dama. Ten stages were defined and, by allocating scores for these stages, the scores that may be expected for a particular age have been identified. Lastly, the predicted age was given for total molariform scores. These were obtained, with 95% prediction intervals, from a regression of age on total molariform scores. An age assessment from tooth development stages can be made up to three years, after which, no further development takes place.