Fig. 5. (A) Drawing of the regions in the muscle slab that illustrate the sign convention for the `added' shear function (Eqn 25 and Eqn 26) and muscle-fibre directions (black arrows, projected onto a transverse plane) that represent roughly the pattern at 51 d.p.f. The boundaries between regions are depicted by horizontal thin green lines. The function is zero at these boundaries. The left side is considered to represent the convex side of the body, and the right side the concave side. Regions with a positive value of are indicated by red + signs, and negative values by blue – signs. The medial myoseptal multilayers of connective tissue in the epaxial and hypaxial muscles (MESP and MHSP) are indicated by thick green horizontal lines. The attachment angles of the muscle fibres that insert at the dorsal and the ventral side of these layers are very different. (B) Contour plot of according to the sign convention of A.