Baron Michel-Edmond de Selys-Longchamps (1813-1900) was a Belgian politician and scientist.   He is widely regarded as the world's greatest authority on dragonflies and damselflies.   His wealth and influence enabled him to amass one of the finest collections of neuropteroid insects and to describe many species from around the world.   Today, his collection is housed in the Belgium National Museum.   This postage stamp is one of four in a series issued on September 29, 1986 to honor famous Belgian scientists.