We frequently find worms in the livers of animals; a description of those found in sheep and oxen is contained in the Journal des Savans of 1668, and in the German Ephimerides. It was thought that these worms were peculiar to animals who chew the cud, but M. Dauberton discovered some in the liver of an ass, and it is probable they might be found in those of many other animals. It has also been said that butterflies are sometimes found in the livers of sheep; and in confirmation of this M. Rouillé favoured me with a letter of M. Gachet de Beaufort, containing the following observations: "It has long been remarked, that our Alpine wedders frequently lose their flesh on a sudden; that their eyes turn white and gummy, that their blood becomes serous, having scarcely any red globules, their tongues parched, and their noses stuffed with a yellow purulent mucus. It is true this does not affect the appetite of the animal, but makes him extremely weak and terminates in his death. From repeated dissections it has been discovered, that animals so affected have always butterflies in their livers, which butterflies are white, and furnished with wings; their heads are nearly oval, hairy, and about the size of those of the silk-worm fly. Above seventy which I squeezed out of the two holes convinced me of the truth of this fact." From this description of M. Beaufort I cannot admit myself as positively convinced of their being butterflies, because they have so near a resemblance to the common worms found in the livers of sheep, which are flat, broad, and of so singular a figure, as to appear at first rather leaves than worms.