The Italian scientist Lazzaro Spallanzani (1729-1799)
is probably best known for his contributions to the debunking of the theory of spontaneous generation.
Yet, among his various scientific interests, Spallanzani also investigated in great detail the ability of various animals to regenerate missing body parts.
In his Prodromo di un opera da imprimersi sopra la riproduzioni
animali published in 1768, Spallanzani reported the regenerative
properties of earthworms and snails, and of the legs, tails and jaws of
aquatic salamanders, as well as the tails of tadpoles and the legs of young
and adult frogs.
In fact, one of his experiments on the regeneration of the head of snails
inspired many people to reproduce this experiment, including Voltaire (1694-1778), who after successfully repeating Spallanzani's experiment would write a letter to Madame du Deffand (who was blind) expressing to her his hope that humans may one day be able to harness this ability. In typical Voltairian humor he would suggest to his friend du Deffand that for many people such a change would be nothing but a great improvement for all concerned parties
(to learn more about the great snail controversy of 1786 in France, and of Lazzaro Spallanzani's influence in the Europe of his time J. Rostand's1951 book Les Origines de la biologie et l'Abbé Spallanzani should be consulted).
A more accessible and very thorough review of Spallanzani's work on regeneration can be found in Charles E. Dinsmore's "A History of Regeneration Research:
Milestones in the Evolution of a Science" published by Cambridge
University Press. The book can also be purchased through Amazon.com