Shelley refers directly to Erasmus Darwin in the "Introduction" to
the 1831 edition of Frankenstein.
Many and long were the conversations between Lord Byron and Shelley, to which I was a devout but nearly silent listener. During one of these, various philosophical doctrines were discussed, and among others the nature of the principle of life, and whether there was any probability of its ever being discovered and communicated. 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. Not thus, after all, would life be given. Perhaps a corpse would be re-animated; galvanism had given token of such things: perhaps the component parts of a creature might be manufactured, brought together, and endured with vital warmth.
Mary acknowledges that they were not discussing the accurate
details of Darwin's experiments, and she then goes on to describe a piece
of pasta (vermicelli) that was reported to have come to life. As Desmond
King-Hele has recently noted, Mary's strange account of Darwin may
derive in part from a passage in the notes to The Temple of Nature
(1802) where Darwin describes "vorticellae" (not vermicelli). Here is that
passage from Darwin's note on spontaneous generation: "Thus the vorticella
or wheel animal, which is found in rain water that has stood some days
in leaden gutters . . .though it discovers no sign of life except when
in the water, yet it is capable of continuing alive for many months though
kept in a dry state" (add. notes 7).