Pyramidal tract and bundle of Bagley in the goat.

In ungulates, very little is known about target areas of the fibers arising in the sensori-motor cortex. King" and Bagley", using the Marchi method, independently reported on projections from the cortical areas which they identified as motor areas by histological and/or electrophysiological methods. Besides the pyramidal tract, the latter author" described that a cortico-tegmental tract (bundle of Bagley) descended through the midbrain and the pontine tegmentum after leaving the cerebral peduncle at the rostral mesencephalon. Recently, Haartsen and Verhaart" investigated the pyramidal and Bagley's tracts in detail using the Nauta method in the goat. Verhaartl" claimed in his monograph that Bagley's bundle was commonly found in ungulates, except for the tubulidentata. He also pointed out that the tract of Bagley was very conspicuous only in artioand perissodactyla. In previous reports on sheeps and goats, no authors have dealt with the projections from the sensori-motor cortex to the upper brain stem. In this study, we examined the corticofugal fibers arising from the anterior and posterior sigmoid gyri to the brain stem and further down to the spinal cord in the goat with the Nauta-Gygax method.