Potato-fly or Potato-rot or Potato-worm

(Entom.), a beetle of several species infesting the potato vine. The Cantharis vittata, which is of a yellowish-red above, barred with black, and the C. atrata, which is wholly black, are common species. They are allied to the Spanish-fly, and are sometimes used for it in the United States. — Potato-rot, a disease of the tubers of the potato. — Potato-worm (Entom.), a large green caterpillar with a horn at its tail, found on potato vines in the United States. It develops into the Sphinx quinquemaculatus.