Santiago Ramón y Cajal shared the 1906 Nobel Prize with Camillo Golgi for their work in neuroanatomy. Cajal proposed that nervous systems were composed of disjunction neurons, while Golgi argued that a nervous system comprised a synticium of fused cells.
Cajal was vindicated in the 1950s by advances in microscopy, but as with so many things in biology, both explanations were right in a way.