Individual Variation.—In several legs, the anterior edge of origin extends forward onto the neural spine of the last free thoracic vertebra. A twig from the middle division of the femoral nerve anastomoses with the typical branch to M. extensor iliotibialis anticus in three legs.
P. p. jamesi
Differences From Typical T. pallidicinctus.—There is no fusion of fibers between M. extensor iliotibialis anticus and M. extensor iliotibialis lateralis.
Individual Variation.—The anterior edge of origin extends forward onto the neural spine of the last free thoracic vertebra in some legs.
Fig. 20. A-D. Dorsal views of M. iliotrochantericus medius, showing its relationship to femoral notch. × 1. In D, note absence of femoral notch and location of branch of femoral nerve. A. Tympanuchus pallidicinctus 2L. B. T. cupido pinnatus 4L. C. Pedioecetes phasianellus jamesi 1L. D. T. pallidicinctus 3L.
E. Medial view of distal end of M. flexor cruris medialis of P. p. jamesi 4L. × 1. Part of insertion is covered by medial collateral ligament.
F,G. Lateral views of posteroproximal corner of M. extensor iliotibialis lateralis (removed from specimen). × 1. F. T. pallidicinctus 2L. G. P. p. jamesi 3L.
H,I. Dorsolateral views of M. piriformis. × 1. H. P. p. jamesi 1L. I. T. cupido attwateri 1L.
J. Lateral view of M. caudofemoralis pars caudifemoralis (removed from specimen) of T. c. pinnatus 4L. × 1. K. Lateral view of extrapelvic part of M. obturator of T. pallidicinctus 3L (bones not shown). × 2.
L,M. Region surrounding obturator foramen of T. pallidicinctus 3L, showing points of attachment of three parts of M. obturator (muscles removed). × 3. L. Lateral view. M. Medial view.
N. Anterior view of left tarsometatarsus of P. p. jamesi 4L, showing dorsal intrinsic muscles of foot. × 1½. Tendon of M. extensor digitorum longus has been removed.