A jar of moles
I love the Grant's Museum. And I love their blog. And this week, I love their specimen of the week. A jar of moles. I looked up the collective nouns for moles; a labour, a movement or a company of moles. None of them really work as well as the simple description of a jar of moles.
I can't add anything except our museums are crammed with interesting things, sometimes those things themselves are crammed.
(Thanks to the Grant's Museum blog for this image. I wish it was mine... both the image and the jar!)