Foetal skin. Coloured scanning electron micrograph (SEM) of skin on the scalp of a human foetus. Here, non-keratinised skin (bright pink, right) is being shed and replaced by the more typical keratinised skin (dusky pink) found in adults. Fine foetal hairs, known as lanugo, are also seen but these are usually shed before birth. These shed cells and skin with sebum make up the vernix caseosa, the waxy white substance found coating the skin of newborn babies. Magnification: x250, when printed 10 centimetres wide.