> Six adult axolotls (including a leucistic specimen) were shipped from Mexico City to the Jardin des Plantes in Paris in 1863. Unaware of their neoteny, Auguste Duméril was surprised when, instead of the axolotl, he found in the vivarium a new species, similar to the salamander. [verification needed] This discovery was the starting point of research about neoteny. It is not certain that Ambystoma velasci specimens were not included in the original shipment. [citation needed] Vilem Laufberger in Prague used thyroid hormone injections to induce an axolotl to grow into a terrestrial adult salamander. The experiment was repeated by Englishman Julian Huxley, who was unaware the experiment had already been done, using ground thyroids. [39] Since then, experiments have been done often with injections of iodine or various thyroid hormones used to induce metamorphosis. [16]