FIGURE 5. Illustration of the the skeleton in the cranial, cervical, and shoulder region of a turtle, modified from Gaffney (1972: Chelydra serpentina) and Herrel et al. (2008: Apalone spinifera). This figure is used to illustrate the orientations of the muscular units in Figure 6, Figure 7, Figure 8, Figure 9, Figure 10, Figure 11, Figure 12, Figure 13, Figure 14, Figure 15. For caption, see Figure 6.  For abbreviations, see Appendix 4 and the abbreviation guide in the text.