Is it quite certain that "no animal can live in the alimentary canal but the parasites which belong to that part of the animal economy?" Being ignorant of the matter I give no opinion, but would bring before your readers' notice the following seemingly well-authenticated instance. I quote from _Insect Transformations_, 1830, p. 239., a work put forth by the Society for the Diffusion of Useful Knowledge. "That insects are, in some rare cases, introduced into the human stomach, has been more than once proved, though the greater number of the accounts of such facts in medical books are too inaccurate to be trusted.[3] But one extraordinary case has been completely authenticated, both by medical men and competent naturalists, and is published in the _Dublin Transactions_, by Dr. Pickells of Cork.[4] Mary Riordan, aged twenty-eight, had been much affected by the death of her mother, and at one of her many visits to the grave seems to have partially lost her senses, having been found lying there on the morning of a winter's day, and having been exposed to heavy rain during the night. When she was about fifteen, two popular Catholic priests had died, and she was told by some old women that if she would drink daily, for a certain time, a quantity of water mixed with clay taken from their graves, she would be for ever secure from disease and sin. Following this absurd and disgusting prescription, she took from time to time large quantities of the draught; some time afterwards, being affected with a burning pain in the stomach (cardialgia), she began to eat large pieces of chalk, which she sometimes also mixed with water and drank.