At a magnification of 42X, this 2005 scanning electron microscopic (SEM) image depicts the morphological characteristics seen at the distal end of a domesticated cat, Felis catus, claw. Arranged in a lamellar, or layered configuration, much the same way as an onion, the claw grows from the inside outward. The older, or outermost layers, are sloughed off as the nail ages. This sloughing process produces what are termed claw husks, which are ghost-like remnants reflecting the overall shape of the original nail. The claw is constructed from keratin, a dense, durable protein, which is also the primary constituent of skin and hair. The outer, hard layered portion of the claw is called the unguis, and the inner, softer, underside layer is termed the subunguis.