DESCRIPTION.--The long slender obturator nerve passes along the oblique iliac crest and divides into several branches immediately before reaching the obturator foramen. One or two branches, which do not pass through the foramen, penetrate the superficial surface of M. obturator pars postica. Several small branches (variable in number and arrangement) pass through the obturator foramen and supply pars ventralis, pars dorsalis, and pars antica of M. obturator. When pars ventralis and pars dorsalis are fused, one branch perforates the proximal end of this mass and reaches pars antica. One large branch passes through the obturator foramen dorsal to the tendon of M. obturator pars postica, then turns ventrally, passing lateral to the latter; the branch passes between Mm. adductor superficialis and adductor profundus and gives twigs to each of these two muscles. INDIVIDUAL VARIATION.--None of significance in any of the three species. =_Sciatic Nerve_=, Figs. 6, 7, 8, 9 _T. pallidicinctus_ DESCRIPTION.--The sciatic nerve passes through the anterior part of the ilio-ischiatic fenestra. Several branches diverge from the nerve immediately after it emerges from the fenestra. The main trunk of the nerve then extends distally through the thigh deep to M. extensor iliofibularis and superficial (lateral) to Mm. flexor ischiofemoralis, caudofemoralis, adductor superficialis, and femorocruralis. The main trunk subdivides into two large nerves--peroneal and tibial--that are adjacent and bound to each other throughout the thigh; the peroneal nerve lies anterior to the tibial. At the distal end of the thigh the main trunk splits grossly into two large branches that diverge and enter the shank. This division does not represent the separation between peroneal and tibial nerves, as is sometimes assumed; the anterior branch includes a part of the tibial nerve as well as the entire peroneal nerve.