Fig. 3. Steady-state flow past the pectoral fin. The position of the fin corresponds to t=0.15 s. (A) Velocity vectors on the surface of the pectoral fin. The vectors are colored according to the magnitude of velocity and are of constant length. The velocity vector is non-dimensionalized with respect to the swimming velocity. (B) Particle traces past a fully extended pectoral fin. Particles are released along a rake parallel to and just upstream of the leading edge of the fin. These particle traces are colored according to the magnitude of velocity.