Figure 2.

Isolated C. morosus femur–tibia joints drive to constant angles after flexion or extension. Photographs of C. morosus returns after flexion (A1) and extension (A2). Lines with open arrows indicate direction of leg movement during passive returns. A3, Mean data. B, Mean data after extensor and flexor muscle ablation. Means and SDs were (muscles intact) postextension, 90 ± 8°, postflexion, 75 ± 6° (muscles ablated), postextension, 142 ± 12°, postflexion, 71 ± 9°. N = 6. Intact and ablated postextension returns differed at p < 0.0001; intact and ablated postflexion returns did not differ (p = 0.99) (repeated measure Student's t test).