Bombardier Beetle
a name applied to many coleopterous insects of the tribe carabidæ. They are divided into two genera the brachinus, and the aptinus; the latter has no membranous wings under the wing sheath. Those found near the tropics are large and brilliantly colored, but those found in this country are generally small. They are called bombardier beetles on account of a remarkable property they possess of violently expelling from the anus a pungent acrid fluid, which, if the species be large, has the power of producing discoloration of the skin, similar to that produced by nitric acid. It also changes blue vegetable colors to red, and then to yellow.