How to tell a Crocus from a Colchicum

Count the stamens. Colchicum have six of them bearing pollen while crocus only have three.

Colchicum montanum, common in the Pyrenees, Spain and Portugal where it can be seen in profusion when the autumn rains bring moisture back to parched hillsides. It is hardy in the open garden here but the flowers are at eye level to slugs and snails! It's a wee thing, only an inch or two high.