In the myenteric plexus of rat stomach, ileum, and rectum, glial cells outnumber nerve cells by more than 3 to 1; they have several processes, extensively branching, which extend between, and adapt themselves to, other cellular elements, constituting a very compact structure. The most prominent feature of glial cell cytoplasm are bundles of gliofilaments. No basement membrane surrounds individual glial cells; a single basement membrane is observed around the whole ganglion. Morphological features do not support the identification of these cells as Schwann cells, but relate them to the central nervous system astrocytes.