Fig. 1. The ovipositor and its muscles in female grasshoppers. (A) Lateral view showing a diagram of dorsal and ventral muscles, apodeme and valvulae. When muscles 271 and 272 contract, the dorsal and ventral valvulae open. (B) Photograph of a dissection showing a dorsal view on the ovipositor opener muscle M271 from a mature female. The tendon at the posterior insertion site appears magenta-coloured. (C) Transverse sections through the apodeme-muscle complex of an immature (<5 day), mature (>14 day) and allatectomised (–CA) female. Note increased size of muscle fibre bundles and apodeme complexity in mature females. A is adapted from Snodgrass (1935) with permission. Scale bars, 1 mm (B); 0.5 mm (C).