Muscle Distribution
The distribution of muscles in the posterior sucker is more complicated than that in the body [19]. Therefore, three samples are treated with muscle relaxation methods before incubation in the fixative solution, while the other two are not treated. Slices of the vertical plane, coronal section and cross section of each sample are obtained, and illustrations of the sectioning planes across the body of suckers shown in Fig 6. Figs Figs7A7A and and8A8A show the coronal and cross sections of the contracted posterior sucker, while Figs Figs9A,9A, 10A and 11A show the vertical plane, coronal section, and cross section slices of the relaxed posterior sucker