The box is thought to have been passed through the generations
Strands of beard hair believed to have been shed by the 19th Century scientist Charles Darwin are to go on display.
It is believed the hair was taken from Darwin's desk in 1882 by female relatives, who were unable to collect a lock of his hair before he was buried.
His great-great grandson Randal Keynes said he found them in a box marked "remaining hair" whilst going through his Shropshire ancestor's possessions.
The hair is part of a Natural History Museum exhibition opening on Friday.
Mr Keynes said he found the hair inside a small leather box, carefully wrapped in tissue paper and stored in an envelope on which Etty Darwin had written: "Found after his death in my father's papers."
It is believed the women of the Darwin household had wanted to take a lock of his head hair, but were unable to do so before the body was removed for burial at Westminster Abbey in 1882.
It is thought they found some scraps of hair at the desk, where the Shrewsbury-born scientist spent many hours writing such works as On the Origin of Species by Means of Natural Selection.
The family believes Darwin's wife, Emma, gave the box to her daughter Annie.
When Annie died aged 10, it is thought the box passed to her younger sister Etty.
The box and its contents will be put on display as part of a Darwin exhibition that includes personal notes he wrote about whether to marry Emma, as well as fossils and zoological specimens.
The exhibition will also include shells Darwin collected on his exploration of South America and the South Pacific islands and oceans.