…what traits Corms have?
Corms have a tunic. The tunic may be fibrous, what botanists call netted or reticulate, or the tunic may be smoother, with distinct rings, what botanists call annulate. Some crocuses have reticulate tunics, and others are annulate, which is one way you can tell crocus species apart.
Corms have a basal plate at the bottom and one or more growing points at the top. Bulbs and corms both have a definite vertical orientation.
Corms are undifferentiated, uniform, and contain no rings when cut apart. Corms are stem tissue, modified and developed to store food.