Sigurdur Hjartarson is missing a human penis. But he’s not worried: four men have promised to donate theirs to him when they die.

Hjartarson is founder and owner of the Icelandic Phallological Museum, which offers visitors from around the world a close-up look at the long and the short of the male reproductive organ…

The largest, from a sperm whale, is 70 kg (154 lb) and 1.7 meters (5.58 ft) long. The smallest, a hamster penis bone, is just 2 mm and must be viewed through a magnifying glass.

One species conspicuous by its absence is homo sapiens, but that may soon be rectified since a German, an American, an Icelander and a Briton have promised to donate their organs after death, according to certificates on display.

He said he began collecting penises 24 years ago, when working as a school administrator, with little notion he would one day be running a museum devoted to the subject.

“It was just a hobby,” he said.

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