Definition of "vermicelli"

They talked of the experiments of Dr. Darwin, (I speak not of what the Doctor really did, or said that he did, but, as more to my purpose, of what was then spoken of as having been done by him,) who preserved a piece of vermicelli in a glass case, till by some extraordinary means it began to move with voluntary motion.

1831 October 15, Mary W[ollstonecraft] Shelley, “Introduction”, in Frankenstein: Or, The Modern Prometheus (Standard Novels; IX), 3rd edition, London: Henry Colburn and Richard Bentley, […], published 31 October 1831, pages ix–x