Bulbs,corms and tubers
J. Agoston (Thu, 17 Jan 2013 13:51:59 PST)

Jim's right, colchicum corms have their buds on the surface, like tubers,
bulbs instead have them between their scales. The basal plate is the
modified stem in bulbs, while in corms the stem is the so called "bulb"
itself. As the stem can't have buds inside, it should be on the surface of
it.

Janos
Z5a, Hungary