The Crab-person of Moldering is a poetic riddle intended to beseech The Corundum, originating in The Harp-Seal of Shying. The rules of the form are applied by poets to produce individual poems which can be recited. The poem is four tercets. Use of internal rhyme is characteristic of the form. A form of parallelism is common throughout the poem, in that certain lines are required to maintain phrasing. Each line has three feet with a syllable weight pattern of short-long-short (quantitative amphibrachic trimeter). The ending of each line of the poem shares the same rhyme.