18CuticleThe cuticle consists of 6 to 8 layers of overlapping scale-likecells arranged so that their free edges point toward the tipof the shaft.16It protects the cortex beneath and acts asa physical barrier against external insult.2It consists of 2parts, the exocuticle and the endocuticle.External to the cuticle is the F-layer, tightly joined tothe cuticle by covalent bonds.5It consists of a single-molecule---thick layer of 18-methyl eicosanoic acid, a highly