Caterpillars do not have facial hair, as we would understand it. They do, however have minute sensory hairs all over their chitinous parts, as the armour-plated chitin has no nerve endings. The hairs are therefore the only way that the caterpillars have of feeling though their chitin. However, if left unchecked, these hairs could grow to a considerable length, which, whilst it could be considered desirable, was occasionally a nuisance, in the same way that stubble could be on a human.
Copyright 1999 Ian Rennie, for Remiel Productions.