Fine details on the surface of human hair.

Synopsis Some previously unreported fine variations in the form of normal hairs are described as they are observed in the scanning electron microscope (SEM). They all arise in the course of surface frictional wear and the chipping away of the hair surface scale edges and include remanent surface impressions of cuticle scale edges, 'false' scale edges, granular surface remnants and highly irregular (chevron) scale patterns. Mechanisms are proposed for the way in which each of these different fine features arise. The paper also contains deliberations on the conditions for operating the SEM consistent with obtaining the best information about the architecture of hair surfaces. The correctness of viewing orientation of scanning electron micrographs is also emphasized to avoid misinterpretation of features on the hair surface.