Decimatus , punishment applied to Roman legionaries in some situations of ineptitude, cowardice or group desertions. The soldiers of the cohorts or army groups involved were divided into groups of 10. The one who of the 10 drew the black pebble in a draw had to be beaten to death or stoned by his own companions. Evidently the punishment did not foster cohesion among peers. Despite its dubious effectiveness as a corrective it was applied on some occasions. For example, when Spartacus' army defeated the soldiers of praetor Claudius Glabro at the foot of Vesuvius because they had not fortified the camp at night.