DeMan (1873) treated the nerves of _Paradisea papuana_, _Corvus monedula_, and the chicken; he also commented briefly on a few other species. Jhering (Ihering, 1873) briefly described the lumbosacral plexus in approximately a dozen birds, but illustrated only two. Gadow (1880) described the nerves in _Struthio_, _Rhea_, and _Casuarius_; his paper contains some excellent illustrations of nerves. Unfortunately, the text is marred by numerous confusing typographical errors. Carlsson (1884) described the nerves of _Eudyptes chrysolopha_, _Alca torda_, _Mergulus alle_, and _Mormon arcticus_. Gadow (1891) described the nerves in a study that included a large variety of birds, but published few illustrations. DuToit (1913) described the lumbosacral plexus of the chicken. Romer (1927) gave the innervation of the hip and thigh muscles in the chicken, but did not cover the lumbosacral plexus. Appleton (1928) gave the innervation, in various birds, only of those muscles of the hip and thigh that are supplied by the tibial and peroneal nerves; he did not include the lumbosacral plexus. Sudilovskaya (1931) described the nerves of _Struthio_, _Rhea_, and _Dromaeus_ (_Dromiceius_). Unfortunately, his illustrations are almost useless as far as the nerves are concerned. Boas (1933) described the lumbosacral plexus in a large number of birds. His extensive account includes numerous good illustrations. Howell (1938) listed the innervation of the hip and thigh muscles in the chicken; he did not include the lumbosacral plexus. Fisher (1946) listed the innervation of the muscles of vultures, but did not include the lumbosacral plexus. Wilcox (1948) gave the innervation of the muscles of _Gavia immer_, but did not include the lumbosacral plexus. Fisher and Goodman (1955) described the nerves in the Whooping Crane. Papers by Chomiak (1950) and Yasuda, _et al._ (1959), both dealing with the chicken, were not examined. MATERIALS AND METHODS Complete dissections of the muscles and nerves were made in eight legs (of five specimens) of the Lesser Prairie Chicken (_Tympanuchus pallidicinctus_), six legs (of four specimens) of the Greater Prairie Chicken (_T. cupido pinnatus_), three legs (of two specimens) of Attwater's Prairie Chicken (_T. cupido attwateri_), and six legs (of four specimens) of the Sharp-tailed Grouse (_Pedioecetes phasianellus jamesi_). For convenience and simplicity of reference, each specimen has been designated by a symbol consisting of the first letter of the genus and of the species (and also of the subspecies in _T. cupido_) plus a number. The letter "L" or "R" is added to indicate the left or right leg. Thus the symbol T.p. 1L refers to the left leg of specimen number one of _T. pallidicinctus_.