Fig. 10. Kinematics of continuous swimming in the final-stage larva of Culex pipiens. (A) Schematic illustration of the larva resting at the surface of the water. Note the respiratory siphon and tracheal gills and associated hairs. (B) Cartoon sequence illustrating a single cycle of swimming movements. The cartoons represent body profiles seen from the dorsal side at 10ms intervals. The horizontal scale has been expanded to allow separation of the profiles. The dot on the animal in position 1 is the centre of the thorax, and the line intersecting it is the transverse axis of the thorax, changes in the orientation of which are illustrated in C. (C) The path of the centre of the thorax (dot) and the transverse axis of the thorax (line) through the water. Note how the axis of the thorax rotates through 132° throughout the half-stroke (compare profiles 1 and 5 in B) and the centre of the thorax tacks from side to side through 48°. The dashed line between B and C links corresponding stages (stage 6).