All the references are to the clothes-moth, which is ubiquitous and extremely plentiful in Palestine. It is almost impossible to guard against its destructiveness, except by constantly using clothes, shawls, carpets, etc. Such goods, when stored for long, are found to be reduced almost to powder on being removed (cf. Job 4:19 etc.). The fragile cases of these moths are referred to in Job 27:18, if the Massoretic Text he correct.
E. W. G. Masterman.