Comparative descriptions of the cranial morphology in living and extinct turtles are presented in this paper. Descriptions are arranged by bone rather than by taxon and attempt to document the types and degrees of differences in cranial structures within the Testudines, emphasizing features of systematic interest. Developmental information is also included. 273 figures supplement the text. About half of these figures show detailed internal morphology and include comparative series showing horizontal and sagittal sections, and oblique views of ear regions for each of the living families of turtles as well as for those extinct families where this information is available. Additional figures, some of which are taken from the literature, show disarticulated elements, inner ear regions, arterial and nerve foramina and canals, and basicranial morphology. The other half of the figures are dorsal, lateral, and ventral views (also occipital views in many cases) of the skull in nearly all living genera of turtles and many extinct genera. The higher category classification used is that developed by Gaffney (1975d) and no taxonomic novelties are announced. A section of text provides a brief literature revew of chelonian systematics and cranial morphology and a listing (by family) of useful turtle skull illustrations from the literature. A revised glossary of anatomical terms and an index are included”–P. 69.

Source: Authors (Gaffney, Eugene S.)  Bulletin of the AMNH: V.164, Article 2