Surface protrusions from the ependymal cells of the median eminence.
D000818:Animals; D001717:Birds / Q000033:anatomy & histology*; D002552:Cerebral Ventricles; D002555:Cerebrospinal Fluid; D004805:Ependyma / Q000166:cytology* / Q000502:physiology; D008854:Microscopy, Electron; D051381:Rats / Q000033:anatomy & histology*