In August, 1886, while visiting in Louisiana, Mo., I made frequent excursions to damp places along a neighboring book in search of butterflies. It was the droughty season, and there were but a few stagnant pools, damp gravel beds, and moist clay slopes at which insects could slake their thirst. At one of the last named places I noticed a great bunch of Coliads (mostly Colias philodice with an occasional Eurytheme), and a few specimens of Pieris rapŒ, which my advance started out put to flight. As a few individuals did not take to wing, but seemed unable to rise though they fluttered violently, my curiosity was aroused and a closer investigation showed the bank and gravel bed below to be strewn with mutilated specimens of Philodice, scores of individuals, detached wings in some cases, in others the head and thorax remained intact.