Absence of a foramen of Magendie in the dog, cat, rabbit, and goat.
D000717:Anatomy, Comparative; D000818:Animals; D001933:Brain Stem / Q000033:anatomy & histology*; D002415:Cats; D002552:Cerebral Ventricles / Q000033:anatomy & histology*; D004285:Dogs; D006041:Goats; D008578:Meninges / Q000033:anatomy & histology*; D011817:Rabbits