Intact teeth were obtained from three cadavers of known age 56, 67, and 76 years, respectively. Cross-sections 100-150 micrometers thick were taken from the roots using a diamond saw. Individual sections were stained, mounted on glass slides, and photographed on a light microscope. The usual number of years for the eruption of any particular tooth were added to the annulation count to determine the estimated age for that cadaver.

Cemental annulations are easily countable in teeth from animals that have an exaggerated regular change of food intake from season to season. Although present in human teeth, cemental annulations are not always easy to count. A method for preparing human teeth for evaluation involving collection, identification, measuring, sectioning, cleaning, acid etching, staining, and mounting is reported. Sections 100-microns thick were stained with cresyl fast violet as a stain of choice and were photographed using standard light microscopic techniques as well as Nomarsky interference microscopy. Countability of annulations from photographic enlargements was evaluated.

Examination of two bowhead whales, Balaena mysticetus, revealed an unusual assembly of reproductive structures. Although the external phenotype was female, the gonads were underdeveloped testes. In the more thoroughly studied of the two whales, all derivatives of the mesonephric (wolffian) and paramesonephric (mtillerian) ducts were absent, and there was an apparently normal male karyotype (40 autosomes + XY). These findings suggest a failure of androgen expression consistent with the syndrome of complete testicular feminization reported in other species. Structural comparisons with two normal male bowheads confirm abnormal development in the two affected whales.

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