Prince William showed enthusiasm today as he opened the Darwin Centre at the Natural History Museum.

Click here to see more pics at Daylife

He did, however, seem less than enthusiastic when asked to hold a large, hairy tarantula just before the official opening.

The arachnid, an eight-inch wide Mexican Red Kneed named Sarah, was being shown to children at the Attenborough Studio when its minders politely asked the Prince if he would like to hold her.

“Ooh, I would love to,” William said, though he certainly didn’t sound like it. But he did hold the tarantula calmly for about a minute.

The Prince later joked about his experience when he opened the Darwin Centre.

“Just to warn you,” he told the audience, “that there is a spider loose somewhere in the Cocoon. It was given to me, and I seem to have lost it. If you see it, it goes by the name of Sarah.”

William admitted he was “petrified” as he held Sarah.

The Natural History Museum’s Darwin Centre is a new 78 million pound section dedicated to the work of Charles Darwin. Both Prince William and naturalist Sir David Attenborough officially opened it.

“I remember coming here first as a child with my mother,” the Prince said in his speech. “Millions of others will have shared with me that same sense of awe and wonder and just a shiver of something more as you step off the street, through the doors, to stare into the beady eye of the blue whale or the terrifying eye socket of a T. Rex. A moment never to be forgotten — especially when everything is a lot bigger than you.”

At one point during the centre’s opening, William stopped by the laboratory, put on a white coat and gloves and was given a demonstration on how scientists work with mosquitoes in order to fight diseases such as malaria.