After the fruitless 1922 "plesiosaur expedition" (more on the expedition Here and Here), during carnival 1923, a float with the shape of a plesiosaur was paraded down Bariloche's main street.
Regarding the whole Plesiosaur issue, some have suggested that the whole issue was made up by a local tycoon, Primo Capraro to promote Bariloche as an international tourist resort and, coincidentially, it was in 1922 that Argentina’s Federal government created the country’s first national park at Nahuel Huapi and set its headquarters in Bariloche.
As the image below shows, he was very active in his advertising: he filtered the news to the press with a sensationalist headline: "The Plesiosaur Captured", but the article actually mentioned the carnival floats.
From: Vallmitjana, R., (2003). Monstruo del lago. Bariloche: Author’s Edition.
 Porcel de Peralta, M. (1969). Biografía del Nahuel-Huapi: La ciudad de los césares, o la ciudad encantada. Bariloche: Editorial Marymar. pp. 165.
 Vallmitjana, R., (2003). Monstruo del lago. Bariloche: Author’s Edition.
Copyright regarding text and everything else excluding the photograph: Copyright 2009 by Austin Whittall © Patagonian Monsters