Stibaropus tabulatus, Schiödte, a Pentatomid bug of the subfamily Cydninae, is remarkable in having the unusual habit of living underground and attacking the roots of tobacco, and to the best of the writer's knowledge this is the first record of this species as an insect of economic importance; though Lefroy has mentioned the allied S. molginus, Schiödte, in his “Indian Insect Life” (p. 674) as having been observed at the roots of a palm in South India at a considerable depth below the surface. As the insect under report was something of a novelty and was a pest of such a valuable crop like tobacco, the writer made special efforts to study its life-history and habits, and it is the aim of this paper to place on record the results of his observations and studies, though he regrets that they are somewhat fragmentary in character.